Oilpan: move 2D Canvas and WebGL objects to the heap.

Source/core/html/canvas/WebGLRenderbuffer.cpp

 /*
  * Copyright (C) 2009 Apple Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 13 matching lines @@
  */
 
 #include "config.h"
 
 #include "core/html/canvas/WebGLRenderbuffer.h"
 
 #include "core/html/canvas/WebGLRenderingContextBase.h"
 
 namespace WebCore {
 
-PassRefPtr<WebGLRenderbuffer> WebGLRenderbuffer::create(WebGLRenderingContextBase* ctx)
+PassRefPtrWillBeRawPtr<WebGLRenderbuffer> WebGLRenderbuffer::create(WebGLRenderingContextBase* ctx)
 {
-    return adoptRef(new WebGLRenderbuffer(ctx));
+    return adoptRefWillBeNoop(new WebGLRenderbuffer(ctx));
 }
 
 WebGLRenderbuffer::~WebGLRenderbuffer()
 {
+#if ENABLE(OILPAN)
+    m_emulatedStencilBuffer.clear();

[haraken, 2014/07/15 15:04:56]

I'm curious why this is needed.

[sof, 2014/07/15 16:23:00]

m_emulatedStencilBuffer is on the heap. If you look at deleteObjectImpl() below,
it tries to force the deletion of its object, which it cannot do.
m_emulatedStencilBuffer (another WebGLRenderbuffer) clears out its own resource
when finalized.

Promptly deleting the stencil buffer is needed if the object is otherwise
deleted/detached, so removing the call to deleteEmulatedStencilBuffer() entirely
is not on for Oilpan.

+#endif
+    detach();
     deleteObject(0);
 }
 
 WebGLRenderbuffer::WebGLRenderbuffer(WebGLRenderingContextBase* ctx)
     : WebGLSharedObject(ctx)
     , m_internalFormat(GL_RGBA4)
     , m_width(0)
     , m_height(0)
     , m_hasEverBeenBound(false)
 {
     ScriptWrappable::init(this);
     setObject(ctx->webContext()->createRenderbuffer());
 }
 
 void WebGLRenderbuffer::deleteObjectImpl(blink::WebGraphicsContext3D* context3d, Platform3DObject object)
 {
     context3d->deleteRenderbuffer(object);
     deleteEmulatedStencilBuffer(context3d);
 }
 
 void WebGLRenderbuffer::deleteEmulatedStencilBuffer(blink::WebGraphicsContext3D* context3d)
 {
     if (!m_emulatedStencilBuffer)
         return;
     m_emulatedStencilBuffer->deleteObject(context3d);
     m_emulatedStencilBuffer.clear();
 }
 
+void WebGLRenderbuffer::trace(Visitor* visitor)
+{
+    visitor->trace(m_emulatedStencilBuffer);
+    WebGLSharedObject::trace(visitor);
 }
+
+}