Histogram the amount of time spent on HTTP(S) page loads

components/page_load_metrics/browser/metrics_web_contents_observer.cc

 // 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.
 
 #include "components/page_load_metrics/browser/metrics_web_contents_observer.h"
 
 #include <algorithm>
 #include <string>
 #include <utility>
 
@@ skipping 283 matching lines @@
 
 void PageLoadTracker::WebContentsHidden() {
   // Only log the first time we background in a given page load.
   if (background_time_.is_null()) {
     // Make sure we either started in the foreground and haven't been
     // foregrounded yet, or started in the background and have already been
     // foregrounded.
     DCHECK_EQ(started_in_foreground_, foreground_time_.is_null());
     background_time_ = base::TimeTicks::Now();
   }
+
+  for (const auto& observer : observers_)
+    observer->OnHidden();
 }
 
 void PageLoadTracker::WebContentsShown() {
   // Only log the first time we foreground in a given page load.
   if (foreground_time_.is_null()) {
     // Make sure we either started in the background and haven't been
     // backgrounded yet, or started in the foreground and have already been
     // backgrounded.
     DCHECK_NE(started_in_foreground_, background_time_.is_null());
     foreground_time_ = base::TimeTicks::Now();
   }
+
+  for (const auto& observer : observers_)
+    observer->OnShown();
 }
 
 void PageLoadTracker::Commit(content::NavigationHandle* navigation_handle) {
   // TODO(bmcquade): To improve accuracy, consider adding commit time to
   // NavigationHandle. Taking a timestamp here should be close enough for now.
   commit_time_ = base::TimeTicks::Now();
   url_ = navigation_handle->GetURL();
   for (const auto& observer : observers_) {
-    observer->OnCommit(navigation_handle);
+    observer->OnCommit(navigation_handle, started_in_foreground_);
   }
   LogAbortChainHistograms(navigation_handle);
 }
 
 void PageLoadTracker::FailedProvisionalLoad(
     content::NavigationHandle* navigation_handle) {
   for (const auto& observer : observers_) {
     observer->OnFailedProvisionalLoad(navigation_handle);
   }
 }
@@ skipping 391 matching lines @@
 
   if (!committed_load_->UpdateTiming(timing, metadata)) {
     // If the page load tracker cannot update its timing, something is wrong
     // with the IPC (it's from another load, or it's invalid in some other way).
     // We expect this to be a rare occurrence.
     RecordInternalError(ERR_BAD_TIMING_IPC);
   }
 }
 
 }  // namespace page_load_metrics