Make WebGL2 objects Oilpan compatible.

Source/core/html/canvas/WebGLSync.cpp

 // Copyright 2015 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.
 
 #include "config.h"
 
 #include "core/html/canvas/WebGLSync.h"
 
 #include "core/html/canvas/WebGL2RenderingContextBase.h"
 
 namespace blink {
 
 WebGLSync::~WebGLSync()
 {
-    deleteObject(0);
+    // Always call detach here to ensure that platform object deletion
+    // happens with Oilpan enabled. It keeps the code regular to do it
+    // with or without Oilpan enabled.
+    //
+    // See comment in WebGLBuffer's destructor for additional
+    // information on why this is done for WebGLSharedObject-derived
+    // objects.
+    detachAndDeleteObject();
 }
 
 WebGLSync::WebGLSync(WebGL2RenderingContextBase* ctx, GLenum objectType)
     : WebGLSharedObject(ctx)
     , m_objectType(objectType)
 {
 }
 
 void WebGLSync::deleteObjectImpl(blink::WebGraphicsContext3D* context3d, Platform3DObject object)
 {
     context3d->deleteSync(object);
 }
 
 } // namespace blink