Remove tons of OILPAN.

sky/engine/platform/heap/Handle.h

Index: sky/engine/platform/heap/Handle.h
diff --git a/sky/engine/platform/heap/Handle.h b/sky/engine/platform/heap/Handle.h
index cb5dad025e5597f27e2c2236d82487fe537d376c..acfe08e4de2e784ac3471de5b3a7c294a42e4d44 100644
--- a/sky/engine/platform/heap/Handle.h
+++ b/sky/engine/platform/heap/Handle.h
@@ -85,24 +85,6 @@
 #define STACK_ALLOCATED() DISALLOW_ALLOCATION()
 #endif
 
-namespace blink {
-
-class Visitor {
-public:
-    template<typename T>
-    void trace(const T* t)
-    {
-    }
-    template<typename T>
-    void trace(T* t)
-    {
-    }
-    template<typename T>
-    void trace(const T& t)
-    {
-    }
-};
-
 #define DECLARE_EMPTY_DESTRUCTOR_WILL_BE_REMOVED(type) \
     public:                                            \
         ~type();                                       \
@@ -118,6 +100,4 @@ public:
 #define DEFINE_STATIC_REF_WILL_BE_PERSISTENT(type, name, arguments) \
     DEFINE_STATIC_REF(type, name, arguments)
 
-} // namespace blink
-
 #endif