Prerender: Remove PerceivedPLT histograms

chrome/browser/prerender/prerender_manager.h

Index: chrome/browser/prerender/prerender_manager.h
diff --git a/chrome/browser/prerender/prerender_manager.h b/chrome/browser/prerender/prerender_manager.h
index 62447f6dc5e2e232fed1191200cb755197a2851d..3614bc6b7b1ca042c69c7b3df69a43a0fecef83b 100644
--- a/chrome/browser/prerender/prerender_manager.h
+++ b/chrome/browser/prerender/prerender_manager.h
@@ -185,23 +185,6 @@ class PrerenderManager : public content::NotificationObserver,
   virtual void MoveEntryToPendingDelete(PrerenderContents* entry,
                                         FinalStatus final_status);
 
-  // Records the page load time for a prerender that wasn't swapped in.
-  void RecordPageLoadTimeNotSwappedIn(Origin origin,
-                                      base::TimeDelta page_load_time,
-                                      const GURL& url);
-
-  // Records the perceived page load time for a page - effectively the time from
-  // when the user navigates to a page to when it finishes loading. The actual
-  // load may have started prior to navigation due to prerender hints.
-  // |fraction_plt_elapsed_at_swap_in| must either be in [0.0, 1.0], or a value
-  // outside that range indicating that it doesn't apply.
-  void RecordPerceivedPageLoadTime(
-      Origin origin,
-      NavigationType navigation_type,
-      base::TimeDelta perceived_page_load_time,
-      double fraction_plt_elapsed_at_swap_in,
-      const GURL& url);
-
   // Called when a NoStatePrefetch request has received a response (including
   // redirects). May be called several times per resource, in case of redirects.
   void RecordPrefetchResponseReceived(Origin origin,
@@ -231,10 +214,11 @@ class PrerenderManager : public content::NotificationObserver,
                                          bool was_hidden,
                                          base::TimeDelta time);
 
-  // Records the perceived first contentful paint time for a prerendered page,
-  // analogous to |RecordPerceivedPageLoadTime|. The FCP ticks is in absolute
-  // time; this has the disadvantage that the histogram will mix browser and
-  // renderer ticks, but there seems to be no way around that.
+  // Records the perceived first contentful paint time for a prerendered page.
+  // The actual load may have started prior to navigation due to prerender
+  // hints. The FCP ticks is in absolute time; this has the disadvantage that
+  // the histogram will mix browser and renderer ticks, but there seems to be no
+  // way around that.
   void RecordPrerenderFirstContentfulPaint(const GURL& url,
                                            content::WebContents* web_contents,
                                            bool is_no_store,