Migrate ProcessesEventRouter to the new task manager

content/public/browser/web_contents_observer.h

Index: content/public/browser/web_contents_observer.h
diff --git a/content/public/browser/web_contents_observer.h b/content/public/browser/web_contents_observer.h
index 7d2fde828928061087ecd84dcba9da76f4485470..4334d8181a68c00cddb10a0f4605b7786e162653 100644
--- a/content/public/browser/web_contents_observer.h
+++ b/content/public/browser/web_contents_observer.h
@@ -27,6 +27,7 @@ class NavigationEntry;
 class NavigationHandle;
 class RenderFrameHost;
 class RenderViewHost;
+class RenderWidgetHost;
 class WebContents;
 class WebContentsImpl;
 struct AXEventNotificationDetails;
@@ -121,6 +122,10 @@ class CONTENT_EXPORT WebContentsObserver : public IPC::Listener,
   virtual void RenderViewHostChanged(RenderViewHost* old_host,
                                      RenderViewHost* new_host) {}
 
+  // This method is invoked when the process for the current main
+  // RenderFrameHost becomes unresponsive.
+  virtual void OnRendererUnresponsive(RenderWidgetHost* render_widget_host) {}
+
   // Navigation related events ------------------------------------------------
 
   // Called when a navigation started in the WebContents. |navigation_handle|