Devtools: UMA for InspectElement loading time was added

chrome/browser/devtools/devtools_window.h

Index: chrome/browser/devtools/devtools_window.h
diff --git a/chrome/browser/devtools/devtools_window.h b/chrome/browser/devtools/devtools_window.h
index b2dfa7f7b06cd3f47495e53d047cad629e1b245f..329fa5dc4d252fba710be998633eb5a8383059c7 100644
--- a/chrome/browser/devtools/devtools_window.h
+++ b/chrome/browser/devtools/devtools_window.h
@@ -298,6 +298,7 @@ class DevToolsWindow : private content::NotificationObserver,
   virtual void CloseWindow() OVERRIDE;
   virtual void SetContentsInsets(
       int left, int top, int right, int bottom) OVERRIDE;
+  virtual void InspectElementCompleted() OVERRIDE;
   virtual void MoveWindow(int x, int y) OVERRIDE;
   virtual void SetIsDocked(bool is_docked) OVERRIDE;
   virtual void OpenInNewTab(const std::string& url) OVERRIDE;
@@ -385,6 +386,7 @@ class DevToolsWindow : private content::NotificationObserver,
 
   scoped_ptr<DevToolsEmbedderMessageDispatcher> embedder_message_dispatcher_;
   base::WeakPtrFactory<DevToolsWindow> weak_factory_;
+  base::TimeTicks inspect_element_start_time_;
   DISALLOW_COPY_AND_ASSIGN(DevToolsWindow);
 };