Remove PageLoad.Timing2.NavigationToCommit histograms.

chrome/browser/page_load_metrics/metrics_web_contents_observer.h

 // Copyright 2015 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_PAGE_LOAD_METRICS_METRICS_WEB_CONTENTS_OBSERVER_H_
 #define CHROME_BROWSER_PAGE_LOAD_METRICS_METRICS_WEB_CONTENTS_OBSERVER_H_
 
 #include <map>
 #include <memory>
 #include <vector>
@@ skipping 183 matching lines @@
   // ABORT_OTHER, and the |abort_cause_time| is within a sufficiently close
   // delta to when it was aborted. Note that only provisional loads can be
   // aborted with ABORT_OTHER. While this heuristic is coarse, it works better
   // and is simpler than other feasible methods. See https://goo.gl/WKRG98.
   bool IsLikelyProvisionalAbort(base::TimeTicks abort_cause_time) const;
 
   bool MatchesOriginalNavigation(content::NavigationHandle* navigation_handle);
 
   // Only valid to call post-commit.
   const GURL& committed_url() const {
-    DCHECK(!commit_time_.is_null());
-    return url_;
+    DCHECK(!committed_url_.is_empty());
+    return committed_url_;
   }
 
   base::TimeTicks navigation_start() const { return navigation_start_; }
 
   PageLoadExtraInfo ComputePageLoadExtraInfo();
 
   ui::PageTransition page_transition() const { return page_transition_; }
 
  private:
   // This function converts a TimeTicks value taken in the browser process
@@ skipping 19 matching lines @@
   // metrics in DidFinishNavigation.
   bool did_stop_tracking_;
 
   // Whether the application went into the background when this PageLoadTracker
   // was active. This is a temporary boolean for UMA tracking.
   bool app_entered_background_;
 
   // The navigation start in TimeTicks, not the wall time reported by Blink.
   const base::TimeTicks navigation_start_;
 
-  // Time this page load was committed. If this page load hasn't committed,
-  // |commit_time_| will be zero.
-  base::TimeTicks commit_time_;
-
-  // The URL of this page load. This is the provisional url before commit
-  // (before redirects), and the committed url after commit.
-  GURL url_;
+  // The committed URL of this page load.
+  GURL committed_url_;
 
   // The start URL for this page load (before redirects).
   GURL start_url_;
 
   std::unique_ptr<FailedProvisionalLoadInfo> failed_provisional_load_info_;
 
   // Will be ABORT_NONE if we have not aborted this load yet. Otherwise will
   // be the first abort action the user performed.
   UserAbortType abort_type_;
 
@@ skipping 157 matching lines @@
 
   // Has the MWCO observed at least one navigation?
   bool has_navigated_;
 
   DISALLOW_COPY_AND_ASSIGN(MetricsWebContentsObserver);
 };
 
 }  // namespace page_load_metrics
 
 #endif  // CHROME_BROWSER_PAGE_LOAD_METRICS_METRICS_WEB_CONTENTS_OBSERVER_H_