Separate page load metrics for backgrounded pages

components/page_load_metrics/browser/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 COMPONENTS_PAGE_LOAD_METRICS_BROWSER_PAGE_LOAD_METRICS_WEB_CONTENTS_OBSERVER_H_
 #define COMPONENTS_PAGE_LOAD_METRICS_BROWSER_PAGE_LOAD_METRICS_WEB_CONTENTS_OBSERVER_H_
 
 #include "base/macros.h"
 #include "base/time/time.h"
 #include "components/page_load_metrics/common/page_load_timing.h"
@@ skipping 19 matching lines @@
       public content::WebContentsUserData<MetricsWebContentsObserver> {
  public:
   ~MetricsWebContentsObserver() override;
 
   // content::WebContentsObserver implementation:
   bool OnMessageReceived(const IPC::Message& message,
                          content::RenderFrameHost* render_frame_host) override;
   void DidCommitNavigation(
       content::NavigationHandle* navigation_handle) override;
   void RenderProcessGone(base::TerminationStatus status) override;
+  void DidStartNavigation(
+      content::NavigationHandle* navigation_handle) override;
+  void DidFinishLoad(content::RenderFrameHost* render_frame_host,
+                     const GURL& validated_url) override;
+  void DidFailLoad(content::RenderFrameHost* render_frame_host,
+                   const GURL& validated_url,
+                   int error_code,
+                   const base::string16& error_description,
+                   bool was_ignored_by_handler) override;
+
+  void WasShown() override;
+  void WasHidden() override;
 
  private:
   explicit MetricsWebContentsObserver(content::WebContents* web_contents);
   friend class content::WebContentsUserData<MetricsWebContentsObserver>;
   friend class MetricsWebContentsObserverTest;
 
   void OnTimingUpdated(content::RenderFrameHost*, const PageLoadTiming& timing);
   void RecordTimingHistograms();
 
   bool IsRelevantNavigation(content::NavigationHandle* navigation_handle);
 
   // Will be null before any navigations have committed. When a navigation
   // commits we will initialize this as empty.
   scoped_ptr<PageLoadTiming> current_timing_;
 
+  // True if the web contents stayed in the foreground for the entire page load.
+  // We record separate metrics for any web contents that have been
+  // backgrounded, because metrics like layout/paint are delayed artificially
+  // when they occur in the bacground.
+  bool current_navigation_stayed_in_foreground_;
+
+  // True if the previous navigation stayed in the foreground.
+  bool previous_navigation_stayed_in_foreground_;
+
+  // True if the web contents is currently in the foreground.
+  bool in_foreground_;
+
   DISALLOW_COPY_AND_ASSIGN(MetricsWebContentsObserver);
 };
 
 }  // namespace page_load_metrics
 
 #endif  // COMPONENTS_PAGE_LOAD_METRICS_BROWSER_PAGE_LOAD_METRICS_WEB_CONTENTS_OBSERVER_H_