Remove prerender sessionStorage namespace merging (1/2)

chrome/browser/prerender/prerender_histograms.h

Index: chrome/browser/prerender/prerender_histograms.h
diff --git a/chrome/browser/prerender/prerender_histograms.h b/chrome/browser/prerender/prerender_histograms.h
index 94f4baa72ad5509a087797a7fe9d1f46ecba9929..9e08bb9b48c1a33e3485ad357283d92dd98cb640 100644
--- a/chrome/browser/prerender/prerender_histograms.h
+++ b/chrome/browser/prerender/prerender_histograms.h
@@ -9,7 +9,6 @@
 
 #include "base/time/time.h"
 #include "chrome/browser/prerender/prerender_contents.h"
-#include "chrome/browser/prerender/prerender_events.h"
 #include "chrome/browser/prerender/prerender_final_status.h"
 #include "chrome/browser/prerender/prerender_local_predictor.h"
 #include "chrome/browser/prerender/prerender_origin.h"
@@ -100,10 +99,6 @@ class PrerenderHistograms {
   void RecordTimeSinceLastRecentVisit(Origin origin,
                                       base::TimeDelta time) const;
 
-  // Records a prerender event.
-  void RecordEvent(Origin origin, uint8 experiment_id, PrerenderEvent event)
-      const;
-
   // Record a prerender cookie status bitmap. Must be in the range
   // [0, PrerenderContents::kNumCookieStatuses).
   void RecordCookieStatus(Origin origin,