First stab at a test for site isolation metrics_memory_details

chrome/browser/metrics/metrics_memory_details_browsertest.cc

Index: chrome/browser/metrics/metrics_memory_details_browsertest.cc
diff --git a/chrome/browser/metrics/metrics_memory_details_browsertest.cc b/chrome/browser/metrics/metrics_memory_details_browsertest.cc
index d38bfda6c6ea11c221fc75ab99747acb8e6bde9d..e6182d656edf979ef04f2f35de3b81b51f7a03b9 100644
--- a/chrome/browser/metrics/metrics_memory_details_browsertest.cc
+++ b/chrome/browser/metrics/metrics_memory_details_browsertest.cc
@@ -9,6 +9,8 @@
 #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 {
 
@@ -41,6 +43,11 @@ class MetricsMemoryDetailsBrowserTest : public InProcessBrowserTest {
   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);
 };
@@ -58,3 +65,32 @@ IN_PROC_BROWSER_TEST_F(MetricsMemoryDetailsBrowserTest, TestMemoryDetails) {
   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));
+}