| Index: Source/core/frame/FrameOwner.h | 
| diff --git a/Source/core/frame/FrameOwner.h b/Source/core/frame/FrameOwner.h | 
| index 1f19f7d515746772c07f8d1af80468ee1aaa019c..f87a53dc25d0b7f6aa6a6936f85dcc94c848e7bf 100644 | 
| --- a/Source/core/frame/FrameOwner.h | 
| +++ b/Source/core/frame/FrameOwner.h | 
| @@ -6,12 +6,14 @@ | 
| #define FrameOwner_h | 
|  | 
| #include "core/dom/SandboxFlags.h" | 
| +#include "platform/heap/Handle.h" | 
|  | 
| namespace blink { | 
|  | 
| -class FrameOwner { | 
| +class FrameOwner : public WillBeGarbageCollectedMixin { | 
| public: | 
| virtual ~FrameOwner() { } | 
| +    virtual void trace(Visitor*) { } | 
|  | 
| virtual bool isLocal() const = 0; | 
|  | 
|  |