First stab at a test for site isolation metrics_memory_details

chrome/browser/metrics/metrics_memory_details_browsertest.cc

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "chrome/browser/metrics/metrics_memory_details.h"
 
 #include "base/bind_helpers.h"
 #include "base/message_loop/message_loop.h"
 #include "base/test/histogram_tester.h"
 #include "chrome/test/base/in_process_browser_test.h"
 #include "content/public/test/test_utils.h"
+#include "testing/gmock/include/gmock/gmock.h"
+#include "net/dns/mock_host_resolver.h"
 
 namespace {
 
 class TestMemoryDetails : public MetricsMemoryDetails {
  public:
   TestMemoryDetails()
       : MetricsMemoryDetails(base::Bind(&base::DoNothing), nullptr) {}
 
   void StartFetchAndWait() {
     StartFetch(FROM_CHROME_ONLY);
@@ skipping 12 matching lines @@
   DISALLOW_COPY_AND_ASSIGN(TestMemoryDetails);
 };
 
 }  // namespace
 
 class MetricsMemoryDetailsBrowserTest : public InProcessBrowserTest {
  public:
   MetricsMemoryDetailsBrowserTest() {}
   ~MetricsMemoryDetailsBrowserTest() override {}
 
+  void SetUpOnMainThread() override {
+    host_resolver()->AddRule("*", "127.0.0.1");
+    ASSERT_TRUE(embedded_test_server()->InitializeAndWaitUntilReady());
+  }
+
  private:
   DISALLOW_COPY_AND_ASSIGN(MetricsMemoryDetailsBrowserTest);
 };
 
 IN_PROC_BROWSER_TEST_F(MetricsMemoryDetailsBrowserTest, TestMemoryDetails) {
   base::HistogramTester histogram_tester;
 
   scoped_refptr<TestMemoryDetails> details(new TestMemoryDetails);
   details->StartFetchAndWait();
 
   // Memory.Browser histogram should have a single non-0 sample recorded.
   histogram_tester.ExpectTotalCount("Memory.Browser", 1);
   scoped_ptr<base::HistogramSamples> samples(
       histogram_tester.GetHistogramSamplesSinceCreation("Memory.Browser"));
   ASSERT_TRUE(samples);
   EXPECT_NE(0, samples->sum());
 }
+
+IN_PROC_BROWSER_TEST_F(MetricsMemoryDetailsBrowserTest, TestSiteIsolation) {
+  // One page, with a buttload of oopifs.
+  GURL url1 = test_server()->GetUrl("a.com",
+        "cross_site_iframe_factory.html?a(b(a(b,c,d,e,f,g,h)),c,d,e,f,g,h)");
+
+  ui_test_utils::NavigateToURL(browser(), url1);
+
+  // Get the metrics.
+  base::HistogramTester histogram_tester;
+
+  scoped_refptr<TestMemoryDetails> details(new TestMemoryDetails);
+  details->StartFetchAndWait();
+
+  base::HistogramTester::CountsMap expected_metrics;
+  expected_metrics["SiteIsolation.BrowsingInstanceCount"] = 1;
+  expected_metrics["SiteIsolation.CurrentRendererProcessCount"] = 1;
+  expected_metrics["SiteIsolation.IsolateAllSitesProcessCountEstimate"] = 1;
+  expected_metrics["SiteIsolation.IsolateAllSitesProcessCountLowerBound"] = 1;
+  expected_metrics["SiteIsolation.IsolateAllSitesProcessCountNoLimit"] = 1;
+  expected_metrics["SiteIsolation.IsolateAllSitesTotalProcessCountEstimate"] = 1;
+  expected_metrics["SiteIsolation.IsolateHttpsSitesProcessCountEstimate"] = 1;
+  expected_metrics["SiteIsolation.IsolateHttpsSitesProcessCountLowerBound"] = 1;
+  expected_metrics["SiteIsolation.IsolateHttpsSitesProcessCountNoLimit"] = 1;
+  expected_metrics["SiteIsolation.IsolateHttpsSitesTotalProcessCountEstimate"] = 1;
+
+  EXPECT_THAT(histogram_tester.GetTotalCountsForPrefix("SiteIsolation."),
+              testing::ContainerEq(expected_metrics));
+}