[Prerender] Remove the "wash" origin in prerender histograms

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 <stddef.h>
 #include <stdint.h>
 
@@ skipping 68 matching lines @@
   void RecordPerSessionCount(Origin origin, int count) const;
 
   // Record time between two prerender requests.
   void RecordTimeBetweenPrerenderRequests(Origin origin,
                                           base::TimeDelta time) const;
 
   // Record a final status of a prerendered page in a histogram.
   void RecordFinalStatus(Origin origin, FinalStatus final_status) const;
 
   // To be called when a new prerender is added.
-  void RecordPrerender(Origin origin, const GURL& url);
+  void RecordPrerender();
 
   // To be called when a new prerender is started.
   void RecordPrerenderStarted(Origin origin) const;
 
   // To be called when we know how many prerenders are running after starting
   // a prerender.
   void RecordConcurrency(size_t prerender_count) const;
 
   // Called when we swap in a prerender.
   void RecordUsedPrerender(Origin origin) const;
@@ skipping 39 matching lines @@
   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.
   bool WithinWindow() const;
 
-  // Returns whether or not there is currently an origin wash.
-  bool IsOriginWash() const;
-
-  // Origin of the last prerender seen.
-  Origin last_origin_;
-
-  // A boolean indicating that we have recently encountered a combination of
-  // different origins, making an attribution of PPLT's to origins impossible.
-  bool origin_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_;
 
   // Indicates whether we have recorded page load events after the most
   // recent prerender.  These must be initialized to true, so that we don't
   // start recording events before the first prerender occurs.
   bool seen_any_pageload_;
   bool seen_pageload_started_after_prerender_;
 
   base::ThreadChecker thread_checker_;
 
   DISALLOW_COPY_AND_ASSIGN(PrerenderHistograms);
 };
 
 }  // namespace prerender
 
 #endif  // CHROME_BROWSER_PRERENDER_PRERENDER_HISTOGRAMS_H_