Devtools: Margin resizer in overlay experiment

Source/core/inspector/InspectorOverlay.h

 /*
  * Copyright (C) 2011 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  *
  * 1.  Redistributions of source code must retain the above copyright
  *     notice, this list of conditions and the following disclaimer.
  * 2.  Redistributions in binary form must reproduce the above copyright
@@ skipping 45 matching lines @@
 
     DEFINE_INLINE_VIRTUAL_TRACE() { }
 
     class CORE_EXPORT Listener : public WillBeGarbageCollectedMixin {
     public:
         virtual ~Listener() { }
         virtual void overlayResumed() = 0;
         virtual void overlaySteppedOver() = 0;
     };
     virtual void setListener(Listener*) = 0;
+
+    class CORE_EXPORT CSSListener : public WillBeGarbageCollectedMixin {
+    public:
+        virtual ~CSSListener() { }
+        virtual void updateCSSProperty(Node* node, long newValue) { }
+    };
+    virtual void setCSSListener(CSSListener*) = 0;
 };
 
 } // namespace blink
 
 
 #endif // InspectorOverlay_h