Prevent tracking metrics for cases such as 204s and downloads.

chrome/browser/page_load_metrics/page_load_metrics_browsertest.cc

 // Copyright (c) 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 "base/macros.h"
 #include "base/test/histogram_tester.h"
 #include "base/time/time.h"
 #include "chrome/browser/page_load_metrics/metrics_web_contents_observer.h"
 #include "chrome/browser/page_load_metrics/observers/aborts_page_load_metrics_observer.h"
 #include "chrome/browser/page_load_metrics/observers/core_page_load_metrics_observer.h"
@@ skipping 20 matching lines @@
 class PageLoadMetricsBrowserTest : public InProcessBrowserTest {
  public:
   PageLoadMetricsBrowserTest() {}
   ~PageLoadMetricsBrowserTest() override {}
 
  protected:
   void NavigateToUntrackedUrl() {
     ui_test_utils::NavigateToURL(browser(), GURL(url::kAboutBlankURL));
   }
 
+  bool NoPageLoadMetricsRecorded() {
+    return histogram_tester_.GetTotalCountsForPrefix("PageLoad.").empty();
+  }
+
   base::HistogramTester histogram_tester_;
 
   DISALLOW_COPY_AND_ASSIGN(PageLoadMetricsBrowserTest);
 };
 
 void FailAllNetworkTransactions(net::URLRequestContextGetter* getter) {
   DCHECK_CURRENTLY_ON(content::BrowserThread::IO);
   net::HttpCache* cache(
       getter->GetURLRequestContext()->http_transaction_factory()->GetCache());
   DCHECK(cache);
   std::unique_ptr<net::FailingHttpTransactionFactory> factory(
       new net::FailingHttpTransactionFactory(cache->GetSession(),
                                              net::ERR_FAILED));
   // Throw away old version; since this is a browser test, there is no
   // need to restore the old state.
   cache->SetHttpNetworkTransactionFactoryForTesting(std::move(factory));
 }
 
 IN_PROC_BROWSER_TEST_F(PageLoadMetricsBrowserTest, NoNavigation) {
   ASSERT_TRUE(embedded_test_server()->Start());
-
-  histogram_tester_.ExpectTotalCount(internal::kHistogramCommit, 0);
-  histogram_tester_.ExpectTotalCount(internal::kHistogramDomContentLoaded, 0);
-  histogram_tester_.ExpectTotalCount(internal::kHistogramLoad, 0);
-  histogram_tester_.ExpectTotalCount(internal::kHistogramFirstLayout, 0);
+  EXPECT_TRUE(NoPageLoadMetricsRecorded());
 }
 
 IN_PROC_BROWSER_TEST_F(PageLoadMetricsBrowserTest, NewPage) {
   ASSERT_TRUE(embedded_test_server()->Start());
 
   ui_test_utils::NavigateToURL(browser(),
                                embedded_test_server()->GetURL("/title1.html"));
   NavigateToUntrackedUrl();
 
   histogram_tester_.ExpectTotalCount(internal::kHistogramDomContentLoaded, 1);
   histogram_tester_.ExpectTotalCount(internal::kHistogramLoad, 1);
   histogram_tester_.ExpectTotalCount(internal::kHistogramFirstLayout, 1);
   histogram_tester_.ExpectTotalCount(internal::kHistogramParseDuration, 1);
   histogram_tester_.ExpectTotalCount(
       internal::kHistogramParseBlockedOnScriptLoad, 1);
   histogram_tester_.ExpectTotalCount(
       internal::kHistogramParseBlockedOnScriptExecution, 1);
+
+  // Verify that NoPageLoadMetricsRecorded returns false when PageLoad metrics
+  // have been recorded.
+  EXPECT_FALSE(NoPageLoadMetricsRecorded());
 }
 
 IN_PROC_BROWSER_TEST_F(PageLoadMetricsBrowserTest, SamePageNavigation) {
   ASSERT_TRUE(embedded_test_server()->Start());
 
   ui_test_utils::NavigateToURL(browser(),
                                embedded_test_server()->GetURL("/title1.html"));
   ui_test_utils::NavigateToURL(
       browser(), embedded_test_server()->GetURL("/title1.html#hash"));
   NavigateToUntrackedUrl();
@@ skipping 18 matching lines @@
   histogram_tester_.ExpectTotalCount(internal::kHistogramLoad, 2);
   histogram_tester_.ExpectTotalCount(internal::kHistogramFirstLayout, 2);
 }
 
 IN_PROC_BROWSER_TEST_F(PageLoadMetricsBrowserTest, NonHtmlMainResource) {
   ASSERT_TRUE(embedded_test_server()->Start());
 
   ui_test_utils::NavigateToURL(browser(),
                                embedded_test_server()->GetURL("/circle.svg"));
   NavigateToUntrackedUrl();
-
-  histogram_tester_.ExpectTotalCount(internal::kHistogramCommit, 0);
-  histogram_tester_.ExpectTotalCount(page_load_metrics::internal::kErrorEvents,
-                                     0);
+  EXPECT_TRUE(NoPageLoadMetricsRecorded());
 }
 
 IN_PROC_BROWSER_TEST_F(PageLoadMetricsBrowserTest, NonHttpOrHttpsUrl) {
   ASSERT_TRUE(embedded_test_server()->Start());
 
   ui_test_utils::NavigateToURL(browser(), GURL(chrome::kChromeUIVersionURL));
   NavigateToUntrackedUrl();
-
-  histogram_tester_.ExpectTotalCount(internal::kHistogramCommit, 0);
-  histogram_tester_.ExpectTotalCount(page_load_metrics::internal::kErrorEvents,
-                                     0);
+  EXPECT_TRUE(NoPageLoadMetricsRecorded());
 }
 
 IN_PROC_BROWSER_TEST_F(PageLoadMetricsBrowserTest, HttpErrorPage) {
   ASSERT_TRUE(embedded_test_server()->Start());
 
   ui_test_utils::NavigateToURL(
       browser(), embedded_test_server()->GetURL("/page_load_metrics/404.html"));
   NavigateToUntrackedUrl();
-
-  histogram_tester_.ExpectTotalCount(internal::kHistogramCommit, 0);
-  histogram_tester_.ExpectTotalCount(page_load_metrics::internal::kErrorEvents,
-                                     0);
+  EXPECT_TRUE(NoPageLoadMetricsRecorded());
 }
 
 IN_PROC_BROWSER_TEST_F(PageLoadMetricsBrowserTest, ChromeErrorPage) {
   ASSERT_TRUE(embedded_test_server()->Start());
 
   // Configure the network stack to fail all attempted loads with a network
   // error, which will cause Chrome to display an error page.
   scoped_refptr<net::URLRequestContextGetter> url_request_context_getter =
       browser()->profile()->GetRequestContext();
   content::BrowserThread::PostTask(
       content::BrowserThread::IO, FROM_HERE,
       base::Bind(&FailAllNetworkTransactions,
                  base::RetainedRef(url_request_context_getter)));
 
   ui_test_utils::NavigateToURL(browser(),
                                embedded_test_server()->GetURL("/title1.html"));
   NavigateToUntrackedUrl();
+  EXPECT_TRUE(NoPageLoadMetricsRecorded());
+}
 
-  histogram_tester_.ExpectTotalCount(internal::kHistogramCommit, 0);
-  histogram_tester_.ExpectTotalCount(page_load_metrics::internal::kErrorEvents,
-                                     0);
+IN_PROC_BROWSER_TEST_F(PageLoadMetricsBrowserTest, Ignore204Pages) {
+  ASSERT_TRUE(embedded_test_server()->Start());
+
+  ui_test_utils::NavigateToURL(browser(),
+                               embedded_test_server()->GetURL("/page204.html"));
+  NavigateToUntrackedUrl();
+  EXPECT_TRUE(NoPageLoadMetricsRecorded());
+}
+
+IN_PROC_BROWSER_TEST_F(PageLoadMetricsBrowserTest, IgnoreDownloads) {
+  ASSERT_TRUE(embedded_test_server()->Start());
+
+  ui_test_utils::NavigateToURL(
+      browser(), embedded_test_server()->GetURL("/download-test3.gif"));
+  NavigateToUntrackedUrl();
+  EXPECT_TRUE(NoPageLoadMetricsRecorded());
 }
 
 IN_PROC_BROWSER_TEST_F(PageLoadMetricsBrowserTest, PreloadDocumentWrite) {
   ASSERT_TRUE(embedded_test_server()->Start());
 
   ui_test_utils::NavigateToURL(
       browser(), embedded_test_server()->GetURL(
                      "/page_load_metrics/document_write_external_script.html"));
   NavigateToUntrackedUrl();
 
@@ skipping 325 matching lines @@
 
   histogram_tester_.ExpectTotalCount(
       prerender::PrerenderHistograms::GetFirstContentfulPaintHistogramName(
           prerender::ORIGIN_NONE, false, true, base::TimeDelta()),
       1);
   histogram_tester_.ExpectTotalCount(
       prerender::PrerenderHistograms::GetFirstContentfulPaintHistogramName(
           prerender::ORIGIN_NONE, false, false, base::TimeDelta()),
       0);
 }