Add subresource filter page load metrics observer

chrome/browser/subresource_filter/subresource_filter_browsertest.cc

Index: chrome/browser/subresource_filter/subresource_filter_browsertest.cc
diff --git a/chrome/browser/subresource_filter/subresource_filter_browsertest.cc b/chrome/browser/subresource_filter/subresource_filter_browsertest.cc
index 334b702f581bdb3fdedb1a9d6ba7096e684a4cec..9724eae20670359081a1762dfa4dd5a2dcbc01d0 100644
--- a/chrome/browser/subresource_filter/subresource_filter_browsertest.cc
+++ b/chrome/browser/subresource_filter/subresource_filter_browsertest.cc
@@ -17,12 +17,14 @@
 #include "base/test/histogram_tester.h"
 #include "chrome/browser/browser_process.h"
 #include "chrome/browser/metrics/subprocess_metrics_provider.h"
+#include "chrome/browser/page_load_metrics/observers/subresource_filter_metrics_observer.h"
 #include "chrome/browser/safe_browsing/test_safe_browsing_service.h"
 #include "chrome/browser/subresource_filter/test_ruleset_publisher.h"
 #include "chrome/browser/ui/browser.h"
 #include "chrome/browser/ui/browser_commands.h"
 #include "chrome/browser/ui/tabs/tab_strip_model.h"
 #include "chrome/common/chrome_paths.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/safe_browsing_db/test_database_manager.h"
@@ -563,6 +565,25 @@ IN_PROC_BROWSER_TEST_F(SubresourceFilterBrowserTest, NoActivationOnAboutBlank) {
       static_cast<base::Histogram::Sample>(ActivationLevel::ENABLED), 2);
 }
 
+IN_PROC_BROWSER_TEST_F(SubresourceFilterBrowserTest, PageLoadMetrics) {
+  GURL url(GetTestUrl("subresource_filter/frame_with_included_script.html"));
+  ConfigureAsPhishingURL(url);
+
+  ASSERT_NO_FATAL_FAILURE(
+      SetRulesetToDisallowURLsWithPathSuffix("included_script.js"));
+
+  base::HistogramTester histogram_tester;
+  ui_test_utils::NavigateToURL(browser(), url);
+  EXPECT_FALSE(WasParsedScriptElementLoaded(web_contents()->GetMainFrame()));
+
+  // Force a navigation to another page, which flushes page load metrics for the
+  // previous page load.
+  ui_test_utils::NavigateToURL(browser(), GURL(url::kAboutBlankURL));
+
+  histogram_tester.ExpectTotalCount(internal::kHistogramSubresourceFilterCount,
+                                    1);
+}
+
 IN_PROC_BROWSER_TEST_F(SubresourceFilterBrowserTest,
                        PRE_MainFrameActivationOnStartup) {
   SetRulesetToDisallowURLsWithPathSuffix("included_script.js");