Move prerender histograms out of prerender manager.

chrome/browser/prerender/prerender_manager.h

Index: chrome/browser/prerender/prerender_manager.h
===================================================================
--- chrome/browser/prerender/prerender_manager.h	(revision 96057)
+++ chrome/browser/prerender/prerender_manager.h	(working copy)
@@ -8,6 +8,7 @@
 
 #include <list>
 #include <map>
+#include <string>
 #include <vector>
 
 #include "base/hash_tables.h"
@@ -20,6 +21,7 @@
 #include "base/timer.h"
 #include "chrome/browser/prerender/prerender_config.h"
 #include "chrome/browser/prerender/prerender_contents.h"
+#include "chrome/browser/prerender/prerender_final_status.h"
 #include "chrome/browser/prerender/prerender_origin.h"
 #include "googleurl/src/gurl.h"
 
@@ -42,6 +44,7 @@
 namespace prerender {
 
 class PrerenderCondition;
+class PrerenderHistograms;
 class PrerenderHistory;
 class PrerenderTracker;
 
@@ -324,26 +327,6 @@
   // Used both on destruction, and when clearing the browing history.
   void DestroyAllContents(FinalStatus final_status);
 
-  // Records the time from when a page starts prerendering to when the user
-  // navigates to it. This must be called on the UI thread.
-  void RecordTimeUntilUsed(base::TimeDelta time_until_used);
-
-  // Composes a histogram name based on a histogram type.
-  std::string ComposeHistogramName(const std::string& prefix_type,
-                                   const std::string& name) const;
-
-  // Returns the histogram name for a given origin and experiment.
-  std::string GetHistogramName(Origin origin, uint8 experiment_id,
-                               const std::string& name) const;
-  // Returns the histogram name for the current window.
-  std::string GetDefaultHistogramName(const std::string& name) const;
-  // Returns the current experiment.
-  uint8 GetCurrentExperimentId() const;
-  // Returns the current origin.
-  Origin GetCurrentOrigin() const;
-  // Returns whether or not there is currently an origin/experiment wash.
-  bool IsOriginExperimentWash() const;
-
   // The configuration.
   Config config_;
 
@@ -383,23 +366,6 @@
 
   static PrerenderManagerMode mode_;
 
-  // An integer indicating a Prerendering Experiment being currently conducted.
-  // (The last experiment ID seen).
-  uint8 last_experiment_id_;
-
-  // Origin of the last prerender seen.
-  Origin last_origin_;
-
-  // A boolean indicating that we have recently encountered a combination of
-  // different experiments and origins, making an attribution of PPLT's to
-  // experiments / origins impossible.
-  bool origin_experiment_wash_;
-
-  // The time when we last saw a prerender request coming from a renderer.
-  // This is used to record perceived PLT's for a certain amount of time
-  // from the point that we last saw a <link rel=prerender> tag.
-  base::TimeTicks last_prerender_seen_time_;
-
   // A count of how many prerenders we do per session. Initialized to 0 then
   // incremented and emitted to a histogram on each successful prerender.
   static int prerenders_per_session_count_;
@@ -422,6 +388,8 @@
 
   std::list<const PrerenderCondition*> prerender_conditions_;
 
+  scoped_ptr<PrerenderHistograms> histograms_;
+
   DISALLOW_COPY_AND_ASSIGN(PrerenderManager);
 };