[Oilpan] Migrate classes under module/webgl onto oilpan heap

Source/modules/webgl/WebGLContextGroup.cpp

 /*
  * Copyright (C) 2011 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 62 matching lines @@
 }
 
 void WebGLContextGroup::addObject(WebGLSharedObject* object)
 {
     m_groupObjects.add(object);
 }
 
 void WebGLContextGroup::detachAndRemoveAllObjects()
 {
     while (!m_groupObjects.isEmpty()) {
-        HashSet<WebGLSharedObject*>::iterator it = m_groupObjects.begin();
+        PersistentHeapHashSet<WeakMember<WebGLSharedObject>>::iterator it = m_groupObjects.begin();
         (*it)->detachContextGroup();
     }
 }
 
 void WebGLContextGroup::loseContextGroup(WebGLRenderingContextBase::LostContextMode mode, WebGLRenderingContextBase::AutoRecoveryMethod autoRecoveryMethod)
 {
     // Detach must happen before loseContextImpl, which destroys the GraphicsContext3D
     // and prevents groupObjects from being properly deleted.
     detachAndRemoveAllObjects();
 
     for (WebGLRenderingContextBase* const context : m_contexts)
         context->loseContextImpl(mode, autoRecoveryMethod);
 }
 
 } // namespace blink