Separate page load metrics for backgrounded pages

components/page_load_metrics/browser/metrics_web_contents_observer.h

Index: components/page_load_metrics/browser/metrics_web_contents_observer.h
diff --git a/components/page_load_metrics/browser/metrics_web_contents_observer.h b/components/page_load_metrics/browser/metrics_web_contents_observer.h
index f0da8e05a4fd3c219d78fc0ddcc67dfd38e80640..a6fd674f588866b9606f9ce6aae2f1b30b7ee23c 100644
--- a/components/page_load_metrics/browser/metrics_web_contents_observer.h
+++ b/components/page_load_metrics/browser/metrics_web_contents_observer.h
@@ -37,6 +37,18 @@ class MetricsWebContentsObserver
   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);
@@ -52,6 +64,18 @@ class MetricsWebContentsObserver
   // 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);
 };