[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 4b9af621ffb4071e7c608effc8fd2ede6f6b1ec0..2df23228baff83c999bd915307b69d6e86a868de 100644
--- a/chrome/browser/resource_coordinator/tab_manager.h
+++ b/chrome/browser/resource_coordinator/tab_manager.h
@@ -154,6 +154,12 @@ class TabManager : public TabStripModelObserver {
   // the WebContents could be deleted if the user closed the tab.
   static int64_t IdFromWebContents(content::WebContents* web_contents);
 
+  void StartSessionRestore() { is_during_session_restore_ = true; }

[fmeawad, 2017/06/09 21:02:54]

nit: SessionRestoreStarted since we are not actually starting it, but instead
observing the start

[ducbui, 2017/06/10 00:40:16]

I change the name to MarkSessionRestoreStarted() to distinguish it with a check.

+
+  void EndSessionRestore() { is_during_session_restore_ = false; }

[fmeawad, 2017/06/09 21:02:54]

ditto

[ducbui, 2017/06/10 00:40:16]

Done.

+
+  bool IsDuringSessionRestore() const { return is_during_session_restore_; }
+
  private:
   FRIEND_TEST_ALL_PREFIXES(TabManagerTest, PurgeBackgroundRenderer);
   FRIEND_TEST_ALL_PREFIXES(TabManagerTest, ActivateTabResetPurgeState);
@@ -366,6 +372,8 @@ class TabManager : public TabStripModelObserver {
   // List of observers that will receive notifications on state changes.
   base::ObserverList<TabManagerObserver> observers_;
 
+  bool is_during_session_restore_;
+
   // Weak pointer factory used for posting delayed tasks.
   base::WeakPtrFactory<TabManager> weak_ptr_factory_;