DRP metrics observer stop observing after hidden

chrome/browser/page_load_metrics/observers/data_reduction_proxy_metrics_observer.h

Index: chrome/browser/page_load_metrics/observers/data_reduction_proxy_metrics_observer.h
diff --git a/chrome/browser/page_load_metrics/observers/data_reduction_proxy_metrics_observer.h b/chrome/browser/page_load_metrics/observers/data_reduction_proxy_metrics_observer.h
index a571b5659c0d5546fdb216fca24860517544bf2b..591e9e57723e41f4d0f301aa358066b3f7854184 100644
--- a/chrome/browser/page_load_metrics/observers/data_reduction_proxy_metrics_observer.h
+++ b/chrome/browser/page_load_metrics/observers/data_reduction_proxy_metrics_observer.h
@@ -45,21 +45,27 @@ extern const char kHistogramParseDurationSuffix[];
 
 // Observer responsible for recording core page load metrics releveant to
 // DataReductionProxy.
 class DataReductionProxyMetricsObserver
     : public page_load_metrics::PageLoadMetricsObserver {
  public:
   DataReductionProxyMetricsObserver();
   ~DataReductionProxyMetricsObserver() override;
 
   // page_load_metrics::PageLoadMetricsObserver:
+  ObservePolicy OnStart(content::NavigationHandle* navigation_handle,
+                        const GURL& currently_committed_url,
+                        bool started_in_foreground) override;
   ObservePolicy OnCommit(content::NavigationHandle* navigation_handle) override;
+  ObservePolicy OnHidden(
+      const page_load_metrics::PageLoadTiming& timing,
+      const page_load_metrics::PageLoadExtraInfo& info) override;
   void OnComplete(const page_load_metrics::PageLoadTiming& timing,
                   const page_load_metrics::PageLoadExtraInfo& info) override;
   void OnDomContentLoadedEventStart(
       const page_load_metrics::PageLoadTiming& timing,
       const page_load_metrics::PageLoadExtraInfo& info) override;
   void OnLoadEventStart(
       const page_load_metrics::PageLoadTiming& timing,
       const page_load_metrics::PageLoadExtraInfo& info) override;
   void OnFirstLayout(const page_load_metrics::PageLoadTiming& timing,
                      const page_load_metrics::PageLoadExtraInfo& info) override;
@@ -76,20 +82,24 @@ class DataReductionProxyMetricsObserver
       const page_load_metrics::PageLoadExtraInfo& info) override;
   void OnFirstMeaningfulPaint(
       const page_load_metrics::PageLoadTiming& timing,
       const page_load_metrics::PageLoadExtraInfo& info) override;
   void OnParseStart(const page_load_metrics::PageLoadTiming& timing,
                     const page_load_metrics::PageLoadExtraInfo& info) override;
   void OnParseStop(const page_load_metrics::PageLoadTiming& timing,
                    const page_load_metrics::PageLoadExtraInfo& info) override;
 
  private:
+  // Sends the page load information to the pingback client.
+  void SendPingback(const page_load_metrics::PageLoadTiming& timing,
+                    const page_load_metrics::PageLoadExtraInfo& info);
+
   // Gets the default DataReductionProxyPingbackClient. Overridden in testing.
   virtual DataReductionProxyPingbackClient* GetPingbackClient() const;
 
   // Data related to this navigation.
   std::unique_ptr<DataReductionProxyData> data_;
 
   // The browser context this navigation is operating in.
   content::BrowserContext* browser_context_;
 
   DISALLOW_COPY_AND_ASSIGN(DataReductionProxyMetricsObserver);