Move the Widget hierarchy to the Oilpan heap.

Source/web/FrameLoaderClientImpl.cpp

Index: Source/web/FrameLoaderClientImpl.cpp
diff --git a/Source/web/FrameLoaderClientImpl.cpp b/Source/web/FrameLoaderClientImpl.cpp
index 8c2d6826ff54206687e76743271e7ee22987a949..2c98c8a1823f2ed4b822230b28a90e7373d8d608 100644
--- a/Source/web/FrameLoaderClientImpl.cpp
+++ b/Source/web/FrameLoaderClientImpl.cpp
@@ -636,7 +636,7 @@ bool FrameLoaderClientImpl::canCreatePluginWithoutRenderer(const String& mimeTyp
     return m_webFrame->client()->canCreatePluginWithoutRenderer(mimeType);
 }
 
-PassRefPtr<Widget> FrameLoaderClientImpl::createPlugin(
+PassRefPtrWillBeRawPtr<Widget> FrameLoaderClientImpl::createPlugin(
     HTMLPlugInElement* element,
     const KURL& url,
     const Vector<String>& paramNames,
@@ -660,19 +660,27 @@ PassRefPtr<Widget> FrameLoaderClientImpl::createPlugin(
         return nullptr;
 
     // The container takes ownership of the WebPlugin.
-    RefPtr<WebPluginContainerImpl> container =
+    RefPtrWillBeRawPtr<WebPluginContainerImpl> container =
         WebPluginContainerImpl::create(element, webPlugin);
 
-    if (!webPlugin->initialize(container.get()))
+    if (!webPlugin->initialize(container.get())) {
+#if ENABLE(OILPAN)
+        container->dispose();
+#endif
         return nullptr;
+    }
 
-    if (policy != AllowDetachedPlugin && !element->renderer())
+    if (policy != AllowDetachedPlugin && !element->renderer()) {
+#if ENABLE(OILPAN)
+        container->dispose();
+#endif
         return nullptr;
+    }
 
     return container;
 }
 
-PassRefPtr<Widget> FrameLoaderClientImpl::createJavaAppletWidget(
+PassRefPtrWillBeRawPtr<Widget> FrameLoaderClientImpl::createJavaAppletWidget(
     HTMLAppletElement* element,
     const KURL& /* baseURL */,
     const Vector<String>& paramNames,