[v8 gc] Introduce a base class for all objects that can have pending activity

third_party/WebKit/Source/bindings/core/v8/V8GCRoot.h

Index: third_party/WebKit/Source/bindings/core/v8/V8GCRoot.h
diff --git a/third_party/WebKit/Source/bindings/core/v8/V8GCRoot.h b/third_party/WebKit/Source/bindings/core/v8/V8GCRoot.h
new file mode 100644
index 0000000000000000000000000000000000000000..f78210246fe1fa8bdb917aa888b9a75c0948e0fd
--- /dev/null
+++ b/third_party/WebKit/Source/bindings/core/v8/V8GCRoot.h
@@ -0,0 +1,29 @@
+// Copyright 2016 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 V8GCRoot_h
+#define V8GCRoot_h
+
+#include "core/CoreExport.h"
+#include "wtf/Noncopyable.h"
+
+namespace blink {
+
+/**
+ * Classes deriving from V8GCRoot will be registered in a thread-specific
+ * list of GC roots. They keep their wrappers and dependant objects alive
+ * as long as they have pending activity.
+ */
+class CORE_EXPORT V8GCRoot {
+    WTF_MAKE_NONCOPYABLE(V8GCRoot);
+public:
+    V8GCRoot();
+
+protected:
+    virtual ~V8GCRoot();
+};
+
+} // namespace blink
+
+#endif // V8GCRoot_h