Remove gc extension from webkit/support

webkit/support/gc_extension.h

Index: webkit/support/gc_extension.h
diff --git a/webkit/support/gc_extension.h b/webkit/support/gc_extension.h
deleted file mode 100644
index 85aaa19564591a04466e651a7eb56e54110112ee..0000000000000000000000000000000000000000
--- a/webkit/support/gc_extension.h
+++ /dev/null
@@ -1,23 +0,0 @@
-// Copyright (c) 2011 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-#ifndef WEBKIT_SUPPORT_GC_EXTENSION_H_
-#define WEBKIT_SUPPORT_GC_EXTENSION_H_
-
-namespace v8 {
-class Extension;
-}
-
-namespace extensions_v8 {
-
-// GCExtension is a v8 extension to expose a method into JS for triggering
-// garbage collection. This should only be used for debugging.
-class GCExtension {
- public:
-  static v8::Extension* Get();
-};
-
-}  // namespace extensions_v8
-
-#endif  // WEBKIT_SUPPORT_GC_EXTENSION_H_