Hang Monitor UMA

content/browser/renderer_host/render_widget_host_impl.h

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef CONTENT_BROWSER_RENDERER_HOST_RENDER_WIDGET_HOST_IMPL_H_
 #define CONTENT_BROWSER_RENDERER_HOST_RENDER_WIDGET_HOST_IMPL_H_
 
 #include <stddef.h>
 #include <stdint.h>
 
@@ skipping 791 matching lines @@
   // by the renderer.
   int in_flight_event_count_;
 
   // Flag to detect recursive calls to GetBackingStore().
   bool in_get_backing_store_;
 
   // Used for UMA histogram logging to measure the time for a repaint view
   // operation to finish.
   base::TimeTicks repaint_start_time_;
 
+  // Used for UMA histogram logging to measure how long the renderer is hanging
+  base::TimeTicks hang_start_time_;
+
   // Set to true if we shouldn't send input events from the render widget.
   bool ignore_input_events_;
 
   // Set when we update the text direction of the selected input element.
   bool text_direction_updated_;
   blink::WebTextDirection text_direction_;
 
   // Set when we cancel updating the text direction.
   // This flag also ignores succeeding update requests until we call
   // NotifyTextDirection().
@@ skipping 106 matching lines @@
   float last_device_scale_factor_;
 
   base::WeakPtrFactory<RenderWidgetHostImpl> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(RenderWidgetHostImpl);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_RENDERER_HOST_RENDER_WIDGET_HOST_IMPL_H_