Remove PageLoad.Timing2.NavigationToCommit histograms.

chrome/browser/page_load_metrics/page_load_metrics_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_PAGE_LOAD_METRICS_OBSERVER_H_
 #define CHROME_BROWSER_PAGE_LOAD_METRICS_PAGE_LOAD_METRICS_OBSERVER_H_
 
 #include "base/macros.h"
 #include "base/optional.h"
 #include "chrome/common/page_load_metrics/page_load_timing.h"
@@ skipping 55 matching lines @@
 };
 
 struct PageLoadExtraInfo {
   PageLoadExtraInfo(
       const base::Optional<base::TimeDelta>& first_background_time,
       const base::Optional<base::TimeDelta>& first_foreground_time,
       bool started_in_foreground,
       bool user_gesture,
       const GURL& committed_url,
       const GURL& start_url,
-      const base::Optional<base::TimeDelta>& time_to_commit,
       UserAbortType abort_type,
       bool abort_user_initiated,
       const base::Optional<base::TimeDelta>& time_to_abort,
       int num_cache_requests,
       int num_network_requests,
       const PageLoadMetadata& metadata);
 
   PageLoadExtraInfo(const PageLoadExtraInfo& other);
 
   ~PageLoadExtraInfo();
@@ skipping 11 matching lines @@
   // bit is true in the renderer.
   const bool user_gesture;
 
   // Committed URL. If the page load did not commit, |committed_url| will be
   // empty.
   const GURL committed_url;
 
   // The URL that started the navigation, before redirects.
   const GURL start_url;
 
-  // Time from navigation start until commit.
-  const base::Optional<base::TimeDelta> time_to_commit;
-
   // The abort time and time to abort for this page load. If the page was not
   // aborted, |abort_type| will be |ABORT_NONE|.
   const UserAbortType abort_type;
 
   // TODO(csharrison): If more metadata for aborts is needed we should provide a
   // better abstraction. Note that this is an approximation.
   bool abort_user_initiated;
 
   const base::Optional<base::TimeDelta> time_to_abort;
 
@@ skipping 106 matching lines @@
   virtual void OnLoadingBehaviorObserved(
       const page_load_metrics::PageLoadExtraInfo& extra_info) {}
 
   // Invoked when the UMA metrics subsystem is persisting metrics as the
   // application goes into the background, on platforms where the browser
   // process may be killed after backgrounding (Android). Implementers should
   // persist any metrics that have been buffered in memory in this callback, as
   // the application may be killed at any time after this method is invoked
   // without further notification. Note that this may be called both for
   // provisional loads as well as committed loads. Implementations that only
-  // want to track committed loads should check extra_info.time_to_commit to
-  // determine if the load had committed. If the implementation returns
-  // CONTINUE_OBSERVING, this method may be called multiple times per observer,
-  // once for each time that the application enters the backround.
+  // want to track committed loads should check whether extra_info.committed_url
+  // is empty to determine if the load had committed. If the implementation
+  // returns CONTINUE_OBSERVING, this method may be called multiple times per
+  // observer, once for each time that the application enters the backround.
   //
   // The default implementation does nothing, and returns CONTINUE_OBSERVING.
   virtual ObservePolicy FlushMetricsOnAppEnterBackground(
       const PageLoadTiming& timing,
       const PageLoadExtraInfo& extra_info);
 
   // One of OnComplete or OnFailedProvisionalLoad is invoked for tracked page
   // loads, immediately before the observer is deleted. These callbacks will not
   // be invoked for page loads that did not meet the criteria for being tracked
   // at the time the navigation completed. The PageLoadTiming struct contains
@@ skipping 12 matching lines @@
   // OnFailedProvisionalLoad is invoked for tracked page loads that did not
   // commit, immediately before the observer is deleted.
   virtual void OnFailedProvisionalLoad(
       const FailedProvisionalLoadInfo& failed_provisional_load_info,
       const PageLoadExtraInfo& extra_info) {}
 };
 
 }  // namespace page_load_metrics
 
 #endif  // CHROME_BROWSER_PAGE_LOAD_METRICS_PAGE_LOAD_METRICS_OBSERVER_H_