Prerender: clarify prerender origin for purposes of FCP histograms.

chrome/browser/prerender/prerender_browsertest.cc

 // Copyright (c) 2012 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 <stddef.h>
 #include <deque>
 #include <set>
 #include <string>
 #include <unordered_map>
 #include <utility>
@@ skipping 3436 matching lines @@
                                             GetActiveWebContents());
   observer.SetNavigationStartTicksForTesting(clock->NowTicks());
 
   page_load_metrics::PageLoadTiming timing;
   timing.navigation_start = base::Time::FromDoubleT(1);  // Non-null time.
   timing.first_contentful_paint = base::TimeDelta::FromMilliseconds(2362);
   page_load_metrics::PageLoadMetricsObserverTestHarness::
       PopulateRequiredTimingFields(&timing);
   observer.OnFirstContentfulPaint(timing, GenericPageLoadExtraInfo(dest_url()));
 
+  // The prerender start will be classified as websame, but the FCP will seen
+  // but not recored (PerceivedTTFCPRecorded = 0) because the prerender was not
+  // swapped in. Nothing should be recorded under ORIGIN_NONE because the
+  // prefetch entry should be created.
   histogram_tester().ExpectTotalCount(
       "Prerender.none_PrefetchTTFCP.Warm.Cacheable.Visible", 0);
   histogram_tester().ExpectTotalCount(
-      "Prerender.none_PerceivedTTFCPRecorded.Visible", 1);
-
-  // Check that the prerender didn't happen with a defined origin.
-  histogram_tester().ExpectTotalCount(
       "Prerender.websame_PrefetchTTFCP.Warm.Cacheable.Visible", 0);
   histogram_tester().ExpectTotalCount(
-      "Prerender.websame_PerceivedTTFCPRecorded.Visible", 0);
-
-  // A FCP is fired by the observer, but as a swap did not occur the perceived
-  // time cannot be calculated, and an unrecorded perceived FCP time histogram
-  // entry is made.
+      "Prerender.none_PerceivedTTFCPRecorded.Visible", 0);
   histogram_tester().ExpectUniqueSample(
-      "Prerender.none_PerceivedTTFCPRecorded.Visible", 0, 1);
+      "Prerender.websame_PerceivedTTFCPRecorded.Visible", 0, 1);
 }
 
 IN_PROC_BROWSER_TEST_F(PrerenderBrowserTest,
                        FirstContentfulPaintTimingTwoPages) {
   GetPrerenderManager()->DisablePageLoadMetricsObserverForTesting();
   base::SimpleTestTickClock* clock = OverridePrerenderManagerTimeTicks();
 
   // As this load will be canceled, it is not waited for, and hence no
   // javascript is executed.
   DisableJavascriptCalls();
@@ skipping 88 matching lines @@
             observer.OnHidden(page_load_metrics::PageLoadTiming(),
                               GenericPageLoadExtraInfo(dest_url())));
 
   page_load_metrics::PageLoadTiming timing;
   timing.navigation_start = base::Time::FromDoubleT(1);  // Non-null time.
   timing.first_contentful_paint = base::TimeDelta::FromMilliseconds(2362);
   page_load_metrics::PageLoadMetricsObserverTestHarness::
       PopulateRequiredTimingFields(&timing);
   observer.OnFirstContentfulPaint(timing, GenericPageLoadExtraInfo(dest_url()));
 
+  // The prerender start will be classified as websame, but the FCP will seen
+  // but not recored (PerceivedTTFCPRecorded = 0) because the prerender was not
+  // swapped in. Nothing should be recorded under ORIGIN_NONE because the
+  // prefetch entry should be created.
   histogram_tester().ExpectTotalCount(
       "Prerender.none_PrefetchTTFCP.Warm.Cacheable.Hidden", 0);
   histogram_tester().ExpectTotalCount(
-      "Prerender.none_PerceivedTTFCPRecorded.Hidden", 1);
-
-  // Check that the prerender didn't happen with a defined origin.
-  histogram_tester().ExpectTotalCount(
       "Prerender.websame_PrefetchTTFCP.Warm.Cacheable.Hidden", 0);
   histogram_tester().ExpectTotalCount(
-      "Prerender.websame_PerceivedTTFCPRecorded.Hidden", 0);
-
-  // A FCP is fired by the observer, but the manager should detect that the
-  // perceived time is not set and so update the following histogram.
+      "Prerender.none_PerceivedTTFCPRecorded.Hidden", 0);
   histogram_tester().ExpectUniqueSample(
-      "Prerender.none_PerceivedTTFCPRecorded.Hidden", 0, 1);
+      "Prerender.websame_PerceivedTTFCPRecorded.Hidden", 0, 1);
 }
 
 // When instantiated, mocks out the global text-to-speech engine with something
 // that emulates speaking any phrase for the duration of 0ms.
 class TtsPlatformMock : public TtsPlatformImpl {
  public:
   TtsPlatformMock() : speaking_requested_(false) {
     TtsController::GetInstance()->SetPlatformImpl(this);
   }
 
@@ skipping 198 matching lines @@
       browser()->tab_strip_model()->GetActiveWebContents();
   bool display_test_result = false;
   ASSERT_TRUE(content::ExecuteScriptAndExtractBool(web_contents,
                                                    "DidDisplayReallyPass()",
                                                    &display_test_result));
   ASSERT_TRUE(display_test_result);
 }
 #endif  // !defined(DISABLE_NACL)
 
 }  // namespace prerender