File: site_details_browsertest.cc

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// Copyright 2015 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include "chrome/browser/site_isolation/site_details.h"

#include <stddef.h>
#include <stdint.h>

#include <memory>
#include <utility>
#include <vector>

#include "base/files/file_path.h"
#include "base/functional/callback_helpers.h"
#include "base/path_service.h"
#include "base/run_loop.h"
#include "base/strings/stringprintf.h"
#include "base/test/metrics/histogram_tester.h"
#include "base/values.h"
#include "build/build_config.h"
#include "chrome/browser/browser_process.h"
#include "chrome/browser/extensions/extension_browsertest.h"
#include "chrome/browser/metrics/metrics_memory_details.h"
#include "chrome/browser/ui/browser.h"
#include "chrome/browser/ui/tabs/tab_strip_model.h"
#include "chrome/common/url_constants.h"
#include "chrome/test/base/in_process_browser_test.h"
#include "chrome/test/base/ui_test_utils.h"
#include "components/metrics/metrics_service.h"
#include "content/public/browser/render_process_host.h"
#include "content/public/browser/spare_render_process_host_manager.h"
#include "content/public/common/content_features.h"
#include "content/public/common/content_switches.h"
#include "content/public/test/back_forward_cache_util.h"
#include "content/public/test/browser_test.h"
#include "content/public/test/browser_test_utils.h"
#include "content/public/test/fenced_frame_test_util.h"
#include "content/public/test/prerender_test_util.h"
#include "content/public/test/test_utils.h"
#include "extensions/common/switches.h"
#include "extensions/test/test_extension_dir.h"
#include "net/dns/mock_host_resolver.h"
#include "net/test/embedded_test_server/embedded_test_server.h"
#include "testing/gmock/include/gmock/gmock.h"
#include "testing/gtest/include/gtest/gtest.h"
#include "third_party/blink/public/common/features.h"

using base::Bucket;
using content::WebContents;
using extensions::Extension;
using extensions::TestExtensionDir;
using testing::ElementsAre;
using testing::PrintToString;

namespace {

class TestMemoryDetails : public MetricsMemoryDetails {
 public:
  TestMemoryDetails() : MetricsMemoryDetails(base::DoNothing()) {}

  TestMemoryDetails(const TestMemoryDetails&) = delete;
  TestMemoryDetails& operator=(const TestMemoryDetails&) = delete;

  void StartFetchAndWait() {
    uma_ = std::make_unique<base::HistogramTester>();
    StartFetch();
    loop_.Run();
  }

  // Returns a HistogramTester which observed the most recent call to
  // StartFetchAndWait().
  base::HistogramTester* uma() { return uma_.get(); }

  int GetOutOfProcessIframeCount() {
    std::vector<Bucket> buckets =
        uma_->GetAllSamples("SiteIsolation.OutOfProcessIframes");
    CHECK_EQ(1U, buckets.size());
    return buckets[0].min;
  }

  int GetOutOfProcessInnerFrameTreesCount() {
    std::vector<Bucket> buckets =
        uma_->GetAllSamples("SiteIsolation.OutOfProcessInnerFrameTrees");
    CHECK_EQ(1U, buckets.size());
    return buckets[0].min;
  }

  size_t CountPageTitles() {
    size_t count = 0;
    for (const ProcessMemoryInformation& process : ChromeBrowser()->processes) {
      if (process.process_type == content::PROCESS_TYPE_RENDERER) {
        count += process.titles.size();
      }
    }
    return count;
  }

 private:
  ~TestMemoryDetails() override = default;

  void OnDetailsAvailable() override {
    MetricsMemoryDetails::OnDetailsAvailable();
    // Exit the loop initiated by StartFetchAndWait().
    loop_.QuitWhenIdle();
  }

  std::unique_ptr<base::HistogramTester> uma_;
  base::RunLoop loop_;
};

// This matcher takes three other matchers as arguments, and applies one of them
// depending on the current site isolation mode. The first applies if no site
// isolation mode is active; the second applies under --isolate-extensions mode;
// and the third applies under --site-per-process mode.
MATCHER_P3(DependingOnPolicy,
           isolate_nothing,
           isolate_extensions,
           isolate_all_sites,
#if BUILDFLAG(IS_ANDROID)
           std::string("(with oopifs disabled) ") +
               PrintToString(isolate_nothing)
#else
           content::AreAllSitesIsolatedForTesting()
               ? std::string("(under --site-per-process) ") +
                     PrintToString(isolate_all_sites)
               : std::string("(under --isolate-extensions) ") +
                     PrintToString(isolate_extensions)
#endif
) {
#if BUILDFLAG(IS_ANDROID)
  return ExplainMatchResult(isolate_nothing, arg, result_listener);
#else
  return content::AreAllSitesIsolatedForTesting()
             ? ExplainMatchResult(isolate_all_sites, arg, result_listener)
             : ExplainMatchResult(isolate_extensions, arg, result_listener);
#endif
}

// Matcher for base::Bucket objects that allows bucket_min to be a matcher.
MATCHER_P2(Sample,
           bucket_min,
           count,
           std::string("is a Bucket whose count is ") + PrintToString(count) +
               std::string(" and whose value is ") +
               PrintToString(bucket_min)) {
  return ExplainMatchResult(count, arg.count, result_listener) &&
         ExplainMatchResult(bucket_min, arg.min, result_listener);
}

// Allow matchers to be pretty-printed when passed to PrintToString() for the
// cases we care about.
template <typename P1, typename P2, typename P3>
void PrintTo(const DependingOnPolicyMatcherP3<P1, P2, P3>& matcher,
             std::ostream* os) {
  testing::Matcher<int> matcherCast = matcher;
  matcherCast.DescribeTo(os);
}

template <typename P1, typename P2>
void PrintTo(const SampleMatcherP2<P1, P2>& matcher, std::ostream* os) {
  testing::Matcher<Bucket> matcherCast = matcher;
  matcherCast.DescribeTo(os);
}

// Matches a container of histogram samples, for the common case where the
// histogram received just one sample.
#define HasOneSample(x) ElementsAre(Sample(x, 1))

}  // namespace

class SiteDetailsBrowserTest : public extensions::ExtensionBrowserTest {
 public:
  SiteDetailsBrowserTest() = default;

  SiteDetailsBrowserTest(const SiteDetailsBrowserTest&) = delete;
  SiteDetailsBrowserTest& operator=(const SiteDetailsBrowserTest&) = delete;

  ~SiteDetailsBrowserTest() override = default;

  void SetUpOnMainThread() override {
    extensions::ExtensionBrowserTest::SetUpOnMainThread();
    host_resolver()->AddRule("*", "127.0.0.1");

    // Add content/test/data so we can use cross_site_iframe_factory.html
    base::FilePath test_data_dir;
    ASSERT_TRUE(
        base::PathService::Get(base::DIR_SRC_TEST_DATA_ROOT, &test_data_dir));
    embedded_test_server()->ServeFilesFromDirectory(
        test_data_dir.AppendASCII("content/test/data/"));
    ASSERT_TRUE(embedded_test_server()->Start());
  }

  // Create and install an extension that has a couple of web-accessible
  // resources and, optionally, a background process.
  const Extension* CreateExtension(const std::string& name,
                                   bool has_background_process) {
    TestExtensionDir dir;

    auto manifest = base::Value::Dict()
                        .Set("name", name)
                        .Set("version", "1.0")
                        .Set("manifest_version", 2)
                        .Set("web_accessible_resources",
                             base::Value::List()
                                 .Append("blank_iframe.html")
                                 .Append("http_iframe.html")
                                 .Append("two_http_iframes.html"));

    if (has_background_process) {
      manifest.Set("background",
                   base::Value::Dict().Set(
                       "scripts", base::Value::List().Append("script.js")));
      dir.WriteFile(FILE_PATH_LITERAL("script.js"),
                    "console.log('" + name + " running');");
    }

    dir.WriteFile(FILE_PATH_LITERAL("blank_iframe.html"),
                  base::StringPrintf("<html><body>%s, blank iframe:"
                                     "  <iframe width=80 height=80></iframe>"
                                     "</body></html>",
                                     name.c_str()));
    std::string iframe_url =
        embedded_test_server()
            ->GetURL("w.com", "/cross_site_iframe_factory.html?w")
            .spec();
    std::string iframe_url2 =
        embedded_test_server()
            ->GetURL("x.com", "/cross_site_iframe_factory.html?x")
            .spec();
    dir.WriteFile(
        FILE_PATH_LITERAL("http_iframe.html"),
        base::StringPrintf("<html><body>%s, http:// iframe:"
                           "  <iframe width=80 height=80 src='%s'></iframe>"
                           "</body></html>",
                           name.c_str(), iframe_url.c_str()));
    dir.WriteFile(FILE_PATH_LITERAL("two_http_iframes.html"),
                  base::StringPrintf(
                      "<html><body>%s, two http:// iframes:"
                      "  <iframe width=80 height=80 src='%s'></iframe>"
                      "  <iframe width=80 height=80 src='%s'></iframe>"
                      "</body></html>",
                      name.c_str(), iframe_url.c_str(), iframe_url2.c_str()));
    dir.WriteManifest(manifest);

    const Extension* extension = LoadExtension(dir.UnpackedPath());
    EXPECT_TRUE(extension);
    temp_dirs_.push_back(std::move(dir));
    return extension;
  }

  const Extension* CreateHostedApp(const std::string& name,
                                   const GURL& app_url) {
    TestExtensionDir dir;

    auto manifest =
        base::Value::Dict()
            .Set("name", name)
            .Set("version", "1.0")
            .Set("manifest_version", 2)
            .Set("app",
                 base::Value::Dict()
                     .Set("urls", base::Value::List().Append(app_url.spec()))
                     .Set("launch",
                          base::Value::Dict().Set("web_url", app_url.spec())));
    dir.WriteManifest(manifest);

    const Extension* extension = LoadExtension(dir.UnpackedPath());
    EXPECT_TRUE(extension);
    temp_dirs_.push_back(std::move(dir));
    return extension;
  }

  int GetRenderProcessCountFromUma(base::HistogramTester* uma) {
    auto buckets = uma->GetAllSamples("Memory.RenderProcessHost.Count2.All");
    EXPECT_EQ(buckets.size(), 1u);
    int rph_count = buckets[0].min;

    // Memory.RenderProcessHost.Count2.All includes all spare processes.
    // Subtract them from total count since the tests below assume no spare.
    rph_count -=
        content::SpareRenderProcessHostManager::Get().GetSpares().size();

    return rph_count;
  }

  int GetRenderProcessCount() {
    return content::RenderProcessHost::GetCurrentRenderProcessCountForTesting();
  }

 private:
  std::vector<TestExtensionDir> temp_dirs_;
};

// Test the accuracy of SiteDetails process estimation, in the presence of
// multiple iframes, navigation, multiple BrowsingInstances, and multiple tabs
// in the same BrowsingInstance.
//
// Disabled since it's flaky: https://crbug.com/830318.
IN_PROC_BROWSER_TEST_F(SiteDetailsBrowserTest, DISABLED_ManyIframes) {
  // Page with 14 nested oopifs across 9 sites (a.com through i.com).
  // None of these are https.
  GURL abcdefghi_url = embedded_test_server()->GetURL(
      "a.com",
      "/cross_site_iframe_factory.html?a(b(a(b,c,d,e,f,g,h)),c,d,e,i(f))");
  ASSERT_TRUE(ui_test_utils::NavigateToURL(browser(), abcdefghi_url));

  // Get the metrics.
  scoped_refptr<TestMemoryDetails> details = new TestMemoryDetails();
  details->StartFetchAndWait();

  EXPECT_EQ(1U, details->CountPageTitles());
  EXPECT_THAT(
      details->uma()->GetAllSamples("SiteIsolation.BrowsingInstanceCount"),
      HasOneSample(1));
  EXPECT_EQ(GetRenderProcessCountFromUma(details->uma()),
            GetRenderProcessCount());
  EXPECT_THAT(GetRenderProcessCount(), DependingOnPolicy(1, 1, 9));
  EXPECT_THAT(details->GetOutOfProcessIframeCount(),
              DependingOnPolicy(0, 0, 14));
  EXPECT_THAT(details->uma()->GetAllSamples("SiteIsolation.ProxyCount"),
              HasOneSample(DependingOnPolicy(0, 0, 114)));
  EXPECT_THAT(details->uma()->GetAllSamples(
                  "SiteIsolation.ProxyCountPerBrowsingInstance"),
              HasOneSample(DependingOnPolicy(0, 0, 114)));

  // Navigate to a different, disjoint set of 7 sites.
  GURL pqrstuv_url = embedded_test_server()->GetURL(
      "p.com",
      "/cross_site_iframe_factory.html?p(q(r),r(s),s(t),t(q),u(u),v(p))");
  ASSERT_TRUE(ui_test_utils::NavigateToURL(browser(), pqrstuv_url));

  details = new TestMemoryDetails();
  details->StartFetchAndWait();

  EXPECT_EQ(1U, details->CountPageTitles());
  EXPECT_THAT(
      details->uma()->GetAllSamples("SiteIsolation.BrowsingInstanceCount"),
      HasOneSample(1));
  EXPECT_EQ(GetRenderProcessCountFromUma(details->uma()),
            GetRenderProcessCount());
  EXPECT_THAT(GetRenderProcessCount(), DependingOnPolicy(1, 1, 7));
  EXPECT_THAT(details->GetOutOfProcessIframeCount(),
              DependingOnPolicy(0, 0, 11));
  EXPECT_THAT(details->uma()->GetAllSamples("SiteIsolation.ProxyCount"),
              HasOneSample(DependingOnPolicy(0, 0, 68)));
  EXPECT_THAT(details->uma()->GetAllSamples(
                  "SiteIsolation.ProxyCountPerBrowsingInstance"),
              HasOneSample(DependingOnPolicy(0, 0, 68)));

  // Open a second tab (different BrowsingInstance) with 4 sites (a through d).
  GURL abcd_url = embedded_test_server()->GetURL(
      "a.com", "/cross_site_iframe_factory.html?a(b(c(d())))");
  ASSERT_TRUE(AddTabAtIndex(1, abcd_url, ui::PAGE_TRANSITION_TYPED));

  details = new TestMemoryDetails();
  details->StartFetchAndWait();

  EXPECT_EQ(2U, details->CountPageTitles());
  EXPECT_THAT(
      details->uma()->GetAllSamples("SiteIsolation.BrowsingInstanceCount"),
      HasOneSample(2));
  EXPECT_EQ(GetRenderProcessCountFromUma(details->uma()),
            GetRenderProcessCount());
  EXPECT_THAT(GetRenderProcessCount(), DependingOnPolicy(2, 2, 11));
  EXPECT_THAT(details->GetOutOfProcessIframeCount(),
              DependingOnPolicy(0, 0, 14));
  EXPECT_THAT(details->uma()->GetAllSamples("SiteIsolation.ProxyCount"),
              HasOneSample(DependingOnPolicy(0, 0, 81)));
  EXPECT_THAT(
      details->uma()->GetAllSamples(
          "SiteIsolation.ProxyCountPerBrowsingInstance"),
      DependingOnPolicy(ElementsAre(Bucket(0, 2)), ElementsAre(Bucket(0, 2)),
                        ElementsAre(Bucket(12, 1), Bucket(68, 1))));

  // Open a third tab (different BrowsingInstance) with the same 4 sites.
  ASSERT_TRUE(AddTabAtIndex(2, abcd_url, ui::PAGE_TRANSITION_TYPED));

  details = new TestMemoryDetails();
  details->StartFetchAndWait();

  EXPECT_THAT(
      details->uma()->GetAllSamples("SiteIsolation.BrowsingInstanceCount"),
      HasOneSample(3));
  EXPECT_EQ(GetRenderProcessCountFromUma(details->uma()),
            GetRenderProcessCount());

  // For --site-per-process, the total process count will be 12 instead of 15,
  // because the third tab's subframes (b, c, d) will reuse matching subframe
  // processes from the second tab (across BrowsingInstances).  This subframe
  // process consolidation was added as part of https://crbug.com/512560.  Note
  // that the a.com main frame in tab 3 won't reuse tab 2's main frame process,
  // so this is still one process higher than the lower bound.
  EXPECT_THAT(GetRenderProcessCount(), DependingOnPolicy(3, 3, 12));

  EXPECT_THAT(details->GetOutOfProcessIframeCount(),
              DependingOnPolicy(0, 0, 17));
  EXPECT_THAT(details->uma()->GetAllSamples("SiteIsolation.ProxyCount"),
              HasOneSample(DependingOnPolicy(0, 0, 96)));
  EXPECT_THAT(
      details->uma()->GetAllSamples(
          "SiteIsolation.ProxyCountPerBrowsingInstance"),
      DependingOnPolicy(ElementsAre(Bucket(0, 3)), ElementsAre(Bucket(0, 3)),
                        ElementsAre(Bucket(12, 2), Bucket(68, 1))));

  // From the third tab, window.open() a fourth tab in the same
  // BrowsingInstance, to a page using the same four sites "a-d" as third tab,
  // plus an additional site "e". The estimated process counts should increase
  // by one (not five) from the previous scenario, as the new tab can reuse the
  // four processes already in the BrowsingInstance.
  GURL dcbae_url = embedded_test_server()->GetURL(
      "a.com", "/cross_site_iframe_factory.html?d(c(b(a(e))))");
  ui_test_utils::UrlLoadObserver load_complete(dcbae_url);
  ASSERT_EQ(3, browser()->tab_strip_model()->count());
  ASSERT_TRUE(
      content::ExecJs(browser()->tab_strip_model()->GetActiveWebContents(),
                      "window.open('" + dcbae_url.spec() + "');"));
  ASSERT_EQ(4, browser()->tab_strip_model()->count());
  load_complete.Wait();

  details = new TestMemoryDetails();
  details->StartFetchAndWait();

  EXPECT_THAT(
      details->uma()->GetAllSamples("SiteIsolation.BrowsingInstanceCount"),
      HasOneSample(3));
  EXPECT_EQ(GetRenderProcessCountFromUma(details->uma()),
            GetRenderProcessCount());
  EXPECT_THAT(GetRenderProcessCount(), DependingOnPolicy(3, 3, 13));
  EXPECT_THAT(details->GetOutOfProcessIframeCount(),
              DependingOnPolicy(0, 0, 21));
  EXPECT_THAT(details->uma()->GetAllSamples("SiteIsolation.ProxyCount"),
              HasOneSample(DependingOnPolicy(0, 0, 114)));
  EXPECT_THAT(details->uma()->GetAllSamples(
                  "SiteIsolation.ProxyCountPerBrowsingInstance"),
              DependingOnPolicy(
                  ElementsAre(Bucket(0, 3)), ElementsAre(Bucket(0, 3)),
                  ElementsAre(Bucket(12, 1), Bucket(29, 1), Bucket(68, 1))));
}

// TODO(crbug.com/40496888): This test is flaky.
IN_PROC_BROWSER_TEST_F(SiteDetailsBrowserTest, DISABLED_IsolateExtensions) {
  // We start on "about:blank", which should be credited with a process in this
  // case.
  scoped_refptr<TestMemoryDetails> details = new TestMemoryDetails();
  details->StartFetchAndWait();
  EXPECT_EQ(GetRenderProcessCountFromUma(details->uma()),
            GetRenderProcessCount());
  EXPECT_THAT(GetRenderProcessCount(), 1);
  EXPECT_EQ(0, details->GetOutOfProcessIframeCount());

  // Install one script-injecting extension with background page, and an
  // extension with web accessible resources.
  const Extension* extension1 = CreateExtension("Extension One", true);
  const Extension* extension2 = CreateExtension("Extension Two", false);

  // Open two a.com tabs (with cross site http iframes). IsolateExtensions mode
  // should have no effect so far, since there are no frames straddling the
  // extension/web boundary.
  GURL tab1_url = embedded_test_server()->GetURL(
      "a.com", "/cross_site_iframe_factory.html?a(b,c)");
  ASSERT_TRUE(ui_test_utils::NavigateToURL(browser(), tab1_url));
  WebContents* tab1 = browser()->tab_strip_model()->GetWebContentsAt(0);
  GURL tab2_url = embedded_test_server()->GetURL(
      "a.com", "/cross_site_iframe_factory.html?a(d,e)");
  ASSERT_TRUE(AddTabAtIndex(1, tab2_url, ui::PAGE_TRANSITION_TYPED));
  WebContents* tab2 = browser()->tab_strip_model()->GetWebContentsAt(1);

  details = new TestMemoryDetails();
  details->StartFetchAndWait();
  EXPECT_EQ(GetRenderProcessCountFromUma(details->uma()),
            GetRenderProcessCount());
  EXPECT_THAT(GetRenderProcessCount(), DependingOnPolicy(3, 3, 7));
  EXPECT_THAT(details->GetOutOfProcessIframeCount(),
              DependingOnPolicy(0, 0, 4));

  // Test that "one process per extension" applies even when web content has an
  // extension iframe.

  // Tab1 navigates its first iframe to a resource of extension1. This shouldn't
  // result in a new extension process (it should share with extension1's
  // background page).
  content::NavigateIframeToURL(
      tab1, "child-0", extension1->ResolveExtensionURL("blank_iframe.html"));
  details = new TestMemoryDetails();
  details->StartFetchAndWait();
  EXPECT_EQ(GetRenderProcessCountFromUma(details->uma()),
            GetRenderProcessCount());
  EXPECT_THAT(GetRenderProcessCount(), DependingOnPolicy(3, 3, 6));
  EXPECT_THAT(details->GetOutOfProcessIframeCount(),
              DependingOnPolicy(0, 1, 4));

  // Tab2 navigates its first iframe to a resource of extension1. This also
  // shouldn't result in a new extension process (it should share with the
  // background page and the other iframe).
  content::NavigateIframeToURL(
      tab2, "child-0", extension1->ResolveExtensionURL("blank_iframe.html"));
  details = new TestMemoryDetails();
  details->StartFetchAndWait();
  EXPECT_EQ(GetRenderProcessCountFromUma(details->uma()),
            GetRenderProcessCount());
  EXPECT_THAT(GetRenderProcessCount(), DependingOnPolicy(3, 3, 5));
  EXPECT_THAT(details->GetOutOfProcessIframeCount(),
              DependingOnPolicy(0, 2, 4));

  // Tab1 navigates its second iframe to a resource of extension2. This SHOULD
  // result in a new process since extension2 had no existing process.
  content::NavigateIframeToURL(
      tab1, "child-1", extension2->ResolveExtensionURL("blank_iframe.html"));
  details = new TestMemoryDetails();
  details->StartFetchAndWait();
  EXPECT_EQ(GetRenderProcessCountFromUma(details->uma()),
            GetRenderProcessCount());
  EXPECT_THAT(GetRenderProcessCount(), DependingOnPolicy(3, 4, 5));
  EXPECT_THAT(details->GetOutOfProcessIframeCount(),
              DependingOnPolicy(0, 3, 4));

  // Tab2 navigates its second iframe to a resource of extension2. This should
  // share the existing extension2 process.
  content::NavigateIframeToURL(
      tab2, "child-1", extension2->ResolveExtensionURL("blank_iframe.html"));
  details = new TestMemoryDetails();
  details->StartFetchAndWait();
  EXPECT_EQ(GetRenderProcessCountFromUma(details->uma()),
            GetRenderProcessCount());
  EXPECT_THAT(GetRenderProcessCount(), DependingOnPolicy(3, 4, 4));
  EXPECT_THAT(details->GetOutOfProcessIframeCount(),
              DependingOnPolicy(0, 4, 4));

  // Install extension3 (identical config to extension2)
  const Extension* extension3 = CreateExtension("Extension Three", false);

  // Navigate Tab2 to a top-level page from extension3. There are four processes
  // now: one for tab1's main frame, and one for each of the extensions:
  // extension1 has a process because it has a background page; extension2 is
  // used as an iframe in tab1, and extension3 is the top-level frame in tab2.
  ASSERT_TRUE(ui_test_utils::NavigateToURL(
      browser(), extension3->ResolveExtensionURL("blank_iframe.html")));
  details = new TestMemoryDetails();
  details->StartFetchAndWait();
  EXPECT_EQ(GetRenderProcessCountFromUma(details->uma()),
            GetRenderProcessCount());
  EXPECT_THAT(GetRenderProcessCount(), DependingOnPolicy(3, 4, 4));
  EXPECT_THAT(details->GetOutOfProcessIframeCount(),
              DependingOnPolicy(0, 2, 2));

  // Navigate tab2 to a different extension3 page containing a web iframe. The
  // iframe should get its own process. The lower bound number indicates that,
  // in theory, the iframe could share a process with tab1's main frame.
  ASSERT_TRUE(ui_test_utils::NavigateToURL(
      browser(), extension3->ResolveExtensionURL("http_iframe.html")));
  details = new TestMemoryDetails();
  details->StartFetchAndWait();
  EXPECT_EQ(GetRenderProcessCountFromUma(details->uma()),
            GetRenderProcessCount());
  EXPECT_THAT(GetRenderProcessCount(), DependingOnPolicy(3, 5, 5));
  EXPECT_THAT(details->GetOutOfProcessIframeCount(),
              DependingOnPolicy(0, 3, 3));

  // Navigate tab1 to an extension3 page with an extension3 iframe. There should
  // be three processes estimated by IsolateExtensions: one for extension3, one
  // for extension1's background page, and one for the web iframe in tab2.
  browser()->tab_strip_model()->ActivateTabAt(
      0, TabStripUserGestureDetails(
             TabStripUserGestureDetails::GestureType::kOther));
  ASSERT_TRUE(ui_test_utils::NavigateToURL(
      browser(), extension3->ResolveExtensionURL("blank_iframe.html")));
  details = new TestMemoryDetails();
  details->StartFetchAndWait();
  EXPECT_EQ(GetRenderProcessCountFromUma(details->uma()),
            GetRenderProcessCount());
  EXPECT_THAT(GetRenderProcessCount(), DependingOnPolicy(2, 3, 3));
  EXPECT_THAT(details->GetOutOfProcessIframeCount(),
              DependingOnPolicy(0, 1, 1));

  // Now navigate tab1 to an extension3 page with a web iframe. This could share
  // a process with tab2's iframe (the LowerBound number), or it could get its
  // own process (the Estimate number).
  ASSERT_TRUE(ui_test_utils::NavigateToURL(
      browser(), extension3->ResolveExtensionURL("http_iframe.html")));
  details = new TestMemoryDetails();
  details->StartFetchAndWait();
  EXPECT_EQ(GetRenderProcessCountFromUma(details->uma()),
            GetRenderProcessCount());

  // There should be four total renderer processes: one for each of the two web
  // iframes, one for extension3, and one for extension 1's background page.
  // Note that the optimization in https://crbug.com/512560, where subframes
  // that require a dedicated process reuse existing processes where possible,
  // does not apply to web iframes in extensions anymore -- see
  // https://crbug.com/899418.
  EXPECT_THAT(GetRenderProcessCount(), DependingOnPolicy(2, 4, 4));
  EXPECT_THAT(details->GetOutOfProcessIframeCount(),
              DependingOnPolicy(0, 2, 2));
}

// Exercises accounting in the case where an extension has two different-site
// web iframes.
IN_PROC_BROWSER_TEST_F(SiteDetailsBrowserTest, ExtensionWithTwoWebIframes) {
  scoped_refptr<TestMemoryDetails> details = new TestMemoryDetails();
  details->StartFetchAndWait();

  // Install one script-injecting extension with background page, and an
  // extension with web accessible resources.
  const Extension* extension = CreateExtension("Test Extension", false);

  ASSERT_TRUE(ui_test_utils::NavigateToURL(
      browser(), extension->ResolveExtensionURL("two_http_iframes.html")));

  details = new TestMemoryDetails();
  details->StartFetchAndWait();
  EXPECT_EQ(GetRenderProcessCountFromUma(details->uma()),
            GetRenderProcessCount());

  if (content::AreAllSitesIsolatedForTesting()) {
    EXPECT_THAT(GetRenderProcessCount(), DependingOnPolicy(1, 3, 3));
  } else {
    // When full isolation is not turned on, the 2 subframes share a process.
    EXPECT_THAT(GetRenderProcessCount(), DependingOnPolicy(1, 2, 2));
  }

  EXPECT_THAT(details->GetOutOfProcessIframeCount(),
              DependingOnPolicy(0, 2, 2));
}

// Verifies that --isolate-extensions doesn't isolate hosted apps.
//
// Disabled since it's flaky: https://crbug.com/830318.
IN_PROC_BROWSER_TEST_F(SiteDetailsBrowserTest,
                       DISABLED_IsolateExtensionsHostedApps) {
  GURL app_with_web_iframe_url = embedded_test_server()->GetURL(
      "app.org", "/cross_site_iframe_factory.html?app.org(b.com)");
  GURL app_in_web_iframe_url = embedded_test_server()->GetURL(
      "b.com", "/cross_site_iframe_factory.html?b.com(app.org)");

  // No hosted app is installed: app.org just behaves like a normal domain.
  ASSERT_TRUE(ui_test_utils::NavigateToURL(browser(), app_with_web_iframe_url));
  scoped_refptr<TestMemoryDetails> details = new TestMemoryDetails();
  details->StartFetchAndWait();
  EXPECT_EQ(GetRenderProcessCountFromUma(details->uma()),
            GetRenderProcessCount());
  EXPECT_THAT(GetRenderProcessCount(), DependingOnPolicy(1, 1, 2));
  EXPECT_THAT(details->GetOutOfProcessIframeCount(),
              DependingOnPolicy(0, 0, 1));

  ASSERT_TRUE(ui_test_utils::NavigateToURL(browser(), app_in_web_iframe_url));
  details = new TestMemoryDetails();
  details->StartFetchAndWait();
  EXPECT_EQ(GetRenderProcessCountFromUma(details->uma()),
            GetRenderProcessCount());
  EXPECT_THAT(GetRenderProcessCount(), DependingOnPolicy(1, 1, 2));
  EXPECT_THAT(details->GetOutOfProcessIframeCount(),
              DependingOnPolicy(0, 0, 1));

  // Now install app.org as a hosted app.
  CreateHostedApp("App", GURL("http://app.org"));

  // Reload the same two pages, and verify that the hosted app still is not
  // isolated by --isolate-extensions, but is isolated by --site-per-process.
  ASSERT_TRUE(ui_test_utils::NavigateToURL(browser(), app_with_web_iframe_url));
  details = new TestMemoryDetails();
  details->StartFetchAndWait();
  EXPECT_EQ(GetRenderProcessCountFromUma(details->uma()),
            GetRenderProcessCount());
  EXPECT_THAT(GetRenderProcessCount(), DependingOnPolicy(1, 1, 2));
  EXPECT_THAT(details->GetOutOfProcessIframeCount(),
              DependingOnPolicy(0, 0, 1));

  ASSERT_TRUE(ui_test_utils::NavigateToURL(browser(), app_in_web_iframe_url));
  details = new TestMemoryDetails();
  details->StartFetchAndWait();
  EXPECT_EQ(GetRenderProcessCountFromUma(details->uma()),
            GetRenderProcessCount());
  EXPECT_THAT(GetRenderProcessCount(), DependingOnPolicy(1, 1, 2));
  EXPECT_THAT(details->GetOutOfProcessIframeCount(),
              DependingOnPolicy(0, 0, 1));
}

// Verifies that the UMA counter for SiteInstances in a BrowsingInstance is
// correct when using tabs with web pages.
//
// Disabled since it's flaky. https://crbug.com/934900
IN_PROC_BROWSER_TEST_F(SiteDetailsBrowserTest,
                       DISABLED_VerifySiteInstanceCountInBrowsingInstance) {
  // Page with 14 nested oopifs across 9 sites (a.com through i.com).
  GURL abcdefghi_url = embedded_test_server()->GetURL(
      "a.com",
      "/cross_site_iframe_factory.html?a(b(a(b,c,d,e,f,g,h)),c,d,e,i(f))");
  ASSERT_TRUE(ui_test_utils::NavigateToURL(browser(), abcdefghi_url));

  // Get the metrics.
  scoped_refptr<TestMemoryDetails> details = new TestMemoryDetails();
  details->StartFetchAndWait();

  // Since there are no extensions involved, the results in the default case
  // and extensions::IsIsolateExtensionsEnabled() are the same.
  EXPECT_THAT(details->uma()->GetAllSamples(
                  "SiteIsolation.SiteInstancesPerBrowsingInstance"),
              HasOneSample(DependingOnPolicy(1, 1, 9)));
  EXPECT_THAT(details->uma()->GetAllSamples("SiteIsolation.ProxyCount"),
              HasOneSample(DependingOnPolicy(0, 0, 114)));
  EXPECT_THAT(details->uma()->GetAllSamples(
                  "SiteIsolation.ProxyCountPerBrowsingInstance"),
              HasOneSample(DependingOnPolicy(0, 0, 114)));

  // Open another tab through window.open(), which will be in the same
  // BrowsingInstance.
  GURL dcbae_url = embedded_test_server()->GetURL(
      "a.com", "/cross_site_iframe_factory.html?d(c(b(j(k))))");
  ui_test_utils::UrlLoadObserver load_complete(dcbae_url);
  ASSERT_EQ(1, browser()->tab_strip_model()->count());
  ASSERT_TRUE(
      content::ExecJs(browser()->tab_strip_model()->GetActiveWebContents(),
                      "window.open('" + dcbae_url.spec() + "');"));
  ASSERT_EQ(2, browser()->tab_strip_model()->count());
  load_complete.Wait();

  details = new TestMemoryDetails();
  details->StartFetchAndWait();
  EXPECT_THAT(details->uma()->GetAllSamples(
                  "SiteIsolation.SiteInstancesPerBrowsingInstance"),
              HasOneSample(DependingOnPolicy(1, 1, 11)));
  EXPECT_THAT(details->uma()->GetAllSamples("SiteIsolation.ProxyCount"),
              HasOneSample(DependingOnPolicy(0, 0, 160)));
  EXPECT_THAT(details->uma()->GetAllSamples(
                  "SiteIsolation.ProxyCountPerBrowsingInstance"),
              HasOneSample(DependingOnPolicy(0, 0, 160)));

  // Open a tab, which will be in a different BrowsingInstance.
  GURL abcd_url = embedded_test_server()->GetURL(
      "a.com", "/cross_site_iframe_factory.html?a(b(c(d())))");
  ASSERT_TRUE(AddTabAtIndex(1, abcd_url, ui::PAGE_TRANSITION_TYPED));

  details = new TestMemoryDetails();
  details->StartFetchAndWait();
  EXPECT_THAT(
      details->uma()->GetAllSamples(
          "SiteIsolation.SiteInstancesPerBrowsingInstance"),
      DependingOnPolicy(ElementsAre(Sample(1, 2)), ElementsAre(Sample(1, 2)),
                        ElementsAre(Sample(4, 1), Sample(11, 1))));
  EXPECT_THAT(details->uma()->GetAllSamples("SiteIsolation.ProxyCount"),
              HasOneSample(DependingOnPolicy(0, 0, 160)));
  EXPECT_THAT(
      details->uma()->GetAllSamples(
          "SiteIsolation.ProxyCountPerBrowsingInstance"),
      DependingOnPolicy(ElementsAre(Sample(0, 2)), ElementsAre(Sample(0, 2)),
                        ElementsAre(Sample(12, 1), Sample(160, 1))));
}

// Verifies that the UMA counter for SiteInstances in a BrowsingInstance is
// correct when extensions and web pages are mixed together.
//
// Disabled since it's flaky: https://crbug.com/830318.
IN_PROC_BROWSER_TEST_F(
    SiteDetailsBrowserTest,
    DISABLED_VerifySiteInstanceCountInBrowsingInstanceWithExtensions) {
  // Open two a.com tabs (with cross site http iframes). IsolateExtensions mode
  // should have no effect so far, since there are no frames straddling the
  // extension/web boundary.
  GURL tab_url = embedded_test_server()->GetURL(
      "a.com", "/cross_site_iframe_factory.html?a(b,c,d(e))");
  ASSERT_TRUE(ui_test_utils::NavigateToURL(browser(), tab_url));
  WebContents* tab = browser()->tab_strip_model()->GetWebContentsAt(0);
  scoped_refptr<TestMemoryDetails> details = new TestMemoryDetails();
  details->StartFetchAndWait();

  // Since there are no extensions loaded yet, the results in the default case
  // and extensions::IsIsolateExtensionsEnabled() are the same.
  EXPECT_THAT(details->uma()->GetAllSamples(
                  "SiteIsolation.SiteInstancesPerBrowsingInstance"),
              HasOneSample(DependingOnPolicy(1, 1, 5)));

  // Load an extension without a background page, which will avoid creating a
  // BrowsingInstance for it.
  const Extension* extension1 = CreateExtension("Extension One", false);

  // Navigate the tab's first iframe to a resource of the extension. The
  // extension iframe will be put in the same BrowsingInstance as it is part
  // of the frame tree.
  content::NavigateIframeToURL(
      tab, "child-0", extension1->ResolveExtensionURL("blank_iframe.html"));
  details = new TestMemoryDetails();
  details->StartFetchAndWait();
  EXPECT_THAT(details->uma()->GetAllSamples(
                  "SiteIsolation.SiteInstancesPerBrowsingInstance"),
              HasOneSample(DependingOnPolicy(1, 2, 5)));

  // Now load an extension with a background page. This will result in a
  // BrowsingInstance for the background page.
  const Extension* extension2 = CreateExtension("Extension Two", true);
  details = new TestMemoryDetails();
  details->StartFetchAndWait();
  EXPECT_THAT(details->uma()->GetAllSamples(
                  "SiteIsolation.SiteInstancesPerBrowsingInstance"),
              DependingOnPolicy(ElementsAre(Bucket(1, 2)),
                                ElementsAre(Bucket(1, 1), Bucket(2, 1)),
                                ElementsAre(Bucket(1, 1), Bucket(5, 1))));

  // Navigate the second iframe of the tab to the second extension. It should
  // stay in the same BrowsingInstance as the page.
  content::NavigateIframeToURL(
      tab, "child-1", extension2->ResolveExtensionURL("blank_iframe.html"));
  details = new TestMemoryDetails();
  details->StartFetchAndWait();
  EXPECT_THAT(details->uma()->GetAllSamples(
                  "SiteIsolation.SiteInstancesPerBrowsingInstance"),
              DependingOnPolicy(ElementsAre(Bucket(1, 2)),
                                ElementsAre(Bucket(1, 1), Bucket(3, 1)),
                                ElementsAre(Bucket(1, 1), Bucket(5, 1))));
}

class PrerenderSiteDetailsBrowserTest : public InProcessBrowserTest {
 public:
  PrerenderSiteDetailsBrowserTest()
      : prerender_helper_(
            base::BindRepeating(&PrerenderSiteDetailsBrowserTest::web_contents,
                                base::Unretained(this))) {}
  ~PrerenderSiteDetailsBrowserTest() override = default;

  PrerenderSiteDetailsBrowserTest(const PrerenderSiteDetailsBrowserTest&) =
      delete;
  PrerenderSiteDetailsBrowserTest& operator=(
      const PrerenderSiteDetailsBrowserTest&) = delete;

  void SetUp() override {
    prerender_helper_.RegisterServerRequestMonitor(embedded_test_server());
    InProcessBrowserTest::SetUp();
  }
  void SetUpOnMainThread() override {
    ASSERT_TRUE(embedded_test_server()->Start());
  }

 protected:
  content::WebContents* web_contents() const {
    return browser()->tab_strip_model()->GetActiveWebContents();
  }
  content::test::PrerenderTestHelper prerender_helper_;
};

IN_PROC_BROWSER_TEST_F(PrerenderSiteDetailsBrowserTest,
                       MemoryDetailsForPrerender) {
  // Navigate to an initial page.
  auto initial_url = embedded_test_server()->GetURL("/empty.html");
  ASSERT_TRUE(ui_test_utils::NavigateToURL(browser(), initial_url));

  // Load a page in the prerender.
  GURL prerender_url = embedded_test_server()->GetURL("/title2.html");
  content::FrameTreeNodeId host_id =
      prerender_helper_.AddPrerender(prerender_url);
  content::test::PrerenderHostObserver host_observer(*web_contents(), host_id);
  EXPECT_FALSE(host_observer.was_activated());

  scoped_refptr<TestMemoryDetails> details = new TestMemoryDetails();
  details->StartFetchAndWait();
  // Currently we don't collect the title of the prerendering page.
  EXPECT_EQ(1U, details->CountPageTitles());
}

class FencedFrameSiteDetailsBrowserTest : public InProcessBrowserTest {
 public:
  FencedFrameSiteDetailsBrowserTest() = default;
  ~FencedFrameSiteDetailsBrowserTest() override = default;

  FencedFrameSiteDetailsBrowserTest(const FencedFrameSiteDetailsBrowserTest&) =
      delete;
  FencedFrameSiteDetailsBrowserTest& operator=(
      const FencedFrameSiteDetailsBrowserTest&) = delete;

  void SetUpOnMainThread() override {
    host_resolver()->AddRule("*", "127.0.0.1");
    ASSERT_TRUE(embedded_test_server()->Start());
  }

 protected:
  content::test::FencedFrameTestHelper& fenced_frame_test_helper() {
    return fenced_frame_helper_;
  }
  content::WebContents* web_contents() const {
    return browser()->tab_strip_model()->GetActiveWebContents();
  }

 private:
  content::test::FencedFrameTestHelper fenced_frame_helper_;
};

IN_PROC_BROWSER_TEST_F(FencedFrameSiteDetailsBrowserTest,
                       MemoryDetailsForFencedFrame) {
  content::IsolateAllSitesForTesting(base::CommandLine::ForCurrentProcess());
  auto initial_url = embedded_test_server()->GetURL("a.com", "/empty.html");
  ASSERT_TRUE(ui_test_utils::NavigateToURL(browser(), initial_url));

  // Load a fenced frame.
  GURL fenced_frame_url =
      embedded_test_server()->GetURL("b.com", "/fenced_frames/iframe.html");
  content::RenderFrameHost* fenced_frame_host =
      fenced_frame_test_helper().CreateFencedFrame(
          web_contents()->GetPrimaryMainFrame(), fenced_frame_url);
  ASSERT_TRUE(fenced_frame_host);

  scoped_refptr<TestMemoryDetails> details = new TestMemoryDetails();
  details->StartFetchAndWait();
  // Currently we don't collect the title of the fenced frame.
  EXPECT_EQ(1U, details->CountPageTitles());

  // Expect we encountered one fenced frame.
  EXPECT_EQ(1, details->GetOutOfProcessInnerFrameTreesCount());
}

class BackForwardCacheSiteDetailsBrowserTest : public InProcessBrowserTest {
 public:
  BackForwardCacheSiteDetailsBrowserTest() {
    // Enable BackForwardCache.
    feature_list_.InitWithFeaturesAndParameters(
        content::GetDefaultEnabledBackForwardCacheFeaturesForTesting(
            /*ignore_outstanding_network_request=*/false),
        content::GetDefaultDisabledBackForwardCacheFeaturesForTesting());
  }
  ~BackForwardCacheSiteDetailsBrowserTest() override = default;

  BackForwardCacheSiteDetailsBrowserTest(
      const BackForwardCacheSiteDetailsBrowserTest&) = delete;
  BackForwardCacheSiteDetailsBrowserTest& operator=(
      const BackForwardCacheSiteDetailsBrowserTest&) = delete;

  void SetUpOnMainThread() override {
    host_resolver()->AddRule("*", "127.0.0.1");
    ASSERT_TRUE(embedded_test_server()->Start());
  }

 protected:
  content::WebContents* web_contents() const {
    return browser()->tab_strip_model()->GetActiveWebContents();
  }

 private:
  base::test::ScopedFeatureList feature_list_;
};

IN_PROC_BROWSER_TEST_F(BackForwardCacheSiteDetailsBrowserTest,
                       MemoryDetailsForBackForwardCache) {
  const GURL url_a(embedded_test_server()->GetURL("a.com", "/title1.html"));
  const GURL url_b(embedded_test_server()->GetURL("b.com", "/title1.html"));

  EXPECT_EQ(web_contents()->GetVisibility(), content::Visibility::VISIBLE);

  // Navigate to A.
  EXPECT_TRUE(ui_test_utils::NavigateToURL(browser(), url_a));

  // Navigate to B.
  EXPECT_TRUE(ui_test_utils::NavigateToURL(browser(), url_b));

  scoped_refptr<TestMemoryDetails> details = new TestMemoryDetails();
  details->StartFetchAndWait();
  // Currently we don't collect the title of the back forward cache.
  EXPECT_EQ(1U, details->CountPageTitles());
}