[Tab Metrics] Measure FP, FCP and FMP for Foreground Tab during Session Restore

chrome/browser/resource_coordinator/tab_manager.h

Index: chrome/browser/resource_coordinator/tab_manager.h
diff --git a/chrome/browser/resource_coordinator/tab_manager.h b/chrome/browser/resource_coordinator/tab_manager.h
index bdb0452fe209b72c2884184e99619bcf0e5adac8..76c5b51537f9f67f0cd3dd47044e6f0045a1acfa 100644
--- a/chrome/browser/resource_coordinator/tab_manager.h
+++ b/chrome/browser/resource_coordinator/tab_manager.h
@@ -161,6 +161,10 @@ class TabManager : public TabStripModelObserver {
     return is_session_restore_loading_tabs_;
   }
 
+  bool HasSessionRestoreInitialForegroundTabChanged() const {
+    return initial_session_restore_foreground_tab_changed_;
+  }
+
  private:
   FRIEND_TEST_ALL_PREFIXES(TabManagerTest, PurgeBackgroundRenderer);
   FRIEND_TEST_ALL_PREFIXES(TabManagerTest, ActivateTabResetPurgeState);
@@ -388,6 +392,9 @@ class TabManager : public TabStripModelObserver {
   class TabManagerSessionRestoreObserver;
   std::unique_ptr<TabManagerSessionRestoreObserver> session_restore_observer_;
 
+  // Whether the user has switched from the initial foreground tab or not.

[lpy, 2017/06/30 19:13:50]

True if initial foreground tab is switched away.

[ducbui, 2017/06/30 19:38:35]

Done.

+  bool initial_session_restore_foreground_tab_changed_;
+
   // Weak pointer factory used for posting delayed tasks.
   base::WeakPtrFactory<TabManager> weak_ptr_factory_;