Create prerender event histograms by origin & experiment.

chrome/browser/prerender/prerender_histograms.h

 // 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.
 
 #ifndef CHROME_BROWSER_PRERENDER_PRERENDER_HISTOGRAMS_H_
 #define CHROME_BROWSER_PRERENDER_PRERENDER_HISTOGRAMS_H_
 
 #include <string>
 
 #include "base/time/time.h"
@@ skipping 71 matching lines @@
 
   // Record the time since a page was recently visited.
   void RecordTimeSinceLastRecentVisit(Origin origin,
                                       base::TimeDelta time) const;
 
   // Record a percentage of pixels of the final page already in place at
   // swap-in.
   void RecordFractionPixelsFinalAtSwapin(Origin origin, double fraction) const;
 
   // Records a prerender event.
-  void RecordEvent(PrerenderEvent event) const;
+  void RecordEvent(Origin origin, uint8 experiment_id, PrerenderEvent event)
+      const;
 
  private:
   base::TimeTicks GetCurrentTimeTicks() const;
 
   // Returns the time elapsed since the last prerender happened.
   base::TimeDelta GetTimeSinceLastPrerender() const;
 
   // Returns whether the PrerenderManager is currently within the prerender
   // window - effectively, up to 30 seconds after a prerender tag has been
   // observed.
@@ skipping 27 matching lines @@
   // start recording events before the first prerender occurs.
   bool seen_any_pageload_;
   bool seen_pageload_started_after_prerender_;
 
   DISALLOW_COPY_AND_ASSIGN(PrerenderHistograms);
 };
 
 }  // namespace prerender
 
 #endif  // CHROME_BROWSER_PRERENDER_PRERENDER_HISTOGRAMS_H_