[DevTools] Pause input events in WebFrameWidgetImpl while debugging.

Source/web/WebDevToolsAgentImpl.h

Index: Source/web/WebDevToolsAgentImpl.h
diff --git a/Source/web/WebDevToolsAgentImpl.h b/Source/web/WebDevToolsAgentImpl.h
index 7605972ffcb4674a61c27fb44b676f1975fd7772..361fa9c941a676b444ba3fa1ec863b2d8cbda742 100644
--- a/Source/web/WebDevToolsAgentImpl.h
+++ b/Source/web/WebDevToolsAgentImpl.h
@@ -57,6 +57,7 @@ class PlatformKeyboardEvent;
 class PlatformMouseEvent;
 class PlatformTouchEvent;
 class WebDevToolsAgentClient;
+class WebFrameWidgetImpl;
 class WebInputEvent;
 class WebLocalFrameImpl;
 class WebString;
@@ -83,6 +84,8 @@ public:
     void flushPendingProtocolNotifications();
     void dispatchMessageFromFrontend(const String& message);
     void registerAgent(PassOwnPtrWillBeRawPtr<InspectorAgent>);
+    static void webViewImplClosed(WebViewImpl*);
+    static void webFrameWidgetImplClosed(WebFrameWidgetImpl*);
 
     // Instrumentation from web/ layer.
     void didCommitLoadForLocalFrame(LocalFrame*);