Bucket FirstContentfulPaint timing into High/Low res clock buckets

components/page_load_metrics/browser/metrics_web_contents_observer.h

 // 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.
 
 #ifndef COMPONENTS_PAGE_LOAD_METRICS_BROWSER_PAGE_LOAD_METRICS_WEB_CONTENTS_OBSERVER_H_
 #define COMPONENTS_PAGE_LOAD_METRICS_BROWSER_PAGE_LOAD_METRICS_WEB_CONTENTS_OBSERVER_H_
 
 #include "base/containers/scoped_ptr_map.h"
 #include "base/macros.h"
 #include "base/observer_list.h"
@@ skipping 42 matching lines @@
     "PageLoad.Timing2.NavigationToDOMContentLoadedEventFired.Background";
 const char kBackgroundHistogramLoad[] =
     "PageLoad.Timing2.NavigationToLoadEventFired.Background";
 const char kBackgroundHistogramFirstPaint[] =
     "PageLoad.Timing2.NavigationToFirstPaint.Background";
 const char kBackgroundHistogramFirstImagePaint[] =
     "PageLoad.Timing2.NavigationToFirstImagePaint.Background.";
 const char kBackgroundHistogramFirstContentfulPaint[] =
     "PageLoad.Timing2.NavigationToFirstContentfulPaint.Background";
 
+const char kHistogramFirstContentfulPaintHigh[] =
+    "PageLoad.Timing2.NavigationToFirstContentfulPaint.HighResolutionClock";
+const char kHistogramFirstContentfulPaintLow[] =
+    "PageLoad.Timing2.NavigationToFirstContentfulPaint.LowResolutionClock";
+
 const char kHistogramFirstBackground[] =
     "PageLoad.Timing2.NavigationToFirstBackground";
 const char kHistogramFirstForeground[] =
     "PageLoad.Timing2.NavigationToFirstForeground";
 
 const char kProvisionalEvents[] = "PageLoad.Events.Provisional";
 const char kCommittedEvents[] = "PageLoad.Events.Committed";
 const char kBackgroundProvisionalEvents[] =
     "PageLoad.Events.Provisional.Background";
 const char kBackgroundCommittedEvents[] =
@@ skipping 223 matching lines @@
 
   scoped_ptr<PageLoadMetricsEmbedderInterface> embedder_interface_;
   base::ObserverList<PageLoadMetricsObserver, true> observers_;
 
   DISALLOW_COPY_AND_ASSIGN(MetricsWebContentsObserver);
 };
 
 }  // namespace page_load_metrics
 
 #endif  // COMPONENTS_PAGE_LOAD_METRICS_BROWSER_PAGE_LOAD_METRICS_WEB_CONTENTS_OBSERVER_H_