[TooManyTabs] Add TabNavigationThrottle

chrome/browser/resource_coordinator/tab_manager_web_contents_data.h

Index: chrome/browser/resource_coordinator/tab_manager_web_contents_data.h
diff --git a/chrome/browser/resource_coordinator/tab_manager_web_contents_data.h b/chrome/browser/resource_coordinator/tab_manager_web_contents_data.h
index 26749d436abd6e3d17c5804a889b850af9a9e03c..3138705faabe6a19f72e400216aebf910d944755 100644
--- a/chrome/browser/resource_coordinator/tab_manager_web_contents_data.h
+++ b/chrome/browser/resource_coordinator/tab_manager_web_contents_data.h
@@ -32,6 +32,7 @@ class TabManager::WebContentsData
 
   // WebContentsObserver implementation:
   void DidStartLoading() override;
+  void DidStopLoading() override;
   void WebContentsDestroyed() override;
 
   // Returns true if the tab has been discarded to save memory.
@@ -112,6 +113,8 @@ class TabManager::WebContentsData
     int discard_count;
     // Is the tab playing audio?
     bool is_recently_audible;
+    // Has the tab finished loading?
+    bool has_finished_loading;
     // Last time the tab started or stopped playing audio (we record the
     // transition time).
     base::TimeTicks last_audio_change_time;