Add an histogram to differentiate between hang types of the renderer

content/browser/renderer_host/render_widget_host_delegate.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_DELEGATE_H_
 #define CONTENT_BROWSER_RENDERER_HOST_RENDER_WIDGET_HOST_DELEGATE_H_
 
 #include <stdint.h>
 
 #include <vector>
@@ skipping 115 matching lines @@
   // RenderWidgetHost to this function to determine who should ultimately
   // consume the event.  This facilitates keyboard event routing with
   // out-of-process iframes, where multiple RenderWidgetHosts may be involved
   // in rendering a page, yet keyboard events all arrive at the main frame's
   // RenderWidgetHostView.  When a main frame's RenderWidgetHost is passed in,
   // the function returns the focused frame that should consume keyboard
   // events. In all other cases, the function returns back |receiving_widget|.
   virtual RenderWidgetHostImpl* GetFocusedRenderWidgetHost(
       RenderWidgetHostImpl* receiving_widget);
 
+  // Used in histograms to differentiate between the different types of
+  // renderer hang reported by RenderWidgetHostDelegate::RendererUnresponsive.
+  // Only add values at the end, do not delete values.
+  enum RendererUnresponsiveType {
+    RENDERER_UNRESPONSIVE_UNKNOWN = 0,
+    RENDERER_UNRESPONSIVE_IN_FLIGHT_EVENTS = 1,
+    RENDERER_UNRESPONSIVE_DIALOG_CLOSED = 2,
+    RENDERER_UNRESPONSIVE_DIALOG_SUPPRESSED = 3,
+    RENDERER_UNRESPONSIVE_BEFORE_UNLOAD = 4,
+    RENDERER_UNRESPONSIVE_UNLOAD = 5,
+    RENDERER_UNRESPONSIVE_CLOSE_PAGE = 6,
+    RENDERER_UNRESPONSIVE_MAX = RENDERER_UNRESPONSIVE_CLOSE_PAGE,
+  };
+
   // Notification that the renderer has become unresponsive. The
   // delegate can use this notification to show a warning to the user.
-  virtual void RendererUnresponsive(RenderWidgetHostImpl* render_widget_host) {}
+  virtual void RendererUnresponsive(RenderWidgetHostImpl* render_widget_host,
+                                    RendererUnresponsiveType type) {}
 
   // Notification that a previously unresponsive renderer has become
   // responsive again. The delegate can use this notification to end the
   // warning shown to the user.
   virtual void RendererResponsive(RenderWidgetHostImpl* render_widget_host) {}
 
   // Requests to lock the mouse. Once the request is approved or rejected,
   // GotResponseToLockMouseRequest() will be called on the requesting render
   // widget host. |privileged| means that the request is always granted, used
   // for Pepper Flash.
@@ skipping 45 matching lines @@
   // Returns the TextInputManager tracking text input state.
   virtual TextInputManager* GetTextInputManager();
 
  protected:
   virtual ~RenderWidgetHostDelegate() {}
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_RENDERER_HOST_RENDER_WIDGET_HOST_DELEGATE_H_