Oilpan: update WebNotification and WebDOMMediaStreamTrack type conversions

public/web/WebNotification.h

Index: public/web/WebNotification.h
diff --git a/public/web/WebNotification.h b/public/web/WebNotification.h
index d37ab3c1d7081e10a439f8e437bc195c03d97678..3306c1b892d6b91b6be3fb31623afb71c37022c1 100644
--- a/public/web/WebNotification.h
+++ b/public/web/WebNotification.h
@@ -93,9 +93,8 @@ public:
     void dispatchDisplayEvent() { dispatchShowEvent(); }
 
 #if BLINK_IMPLEMENTATION
-    WebNotification(const WTF::PassRefPtr<WebCore::Notification>&);
-    WebNotification& operator=(const WTF::PassRefPtr<WebCore::Notification>&);
-    operator WTF::PassRefPtr<WebCore::Notification>() const;
+    WebNotification(const WTF::RawPtr<WebCore::Notification>&);

[sof, 2014/06/04 21:21:08]

I want to go further here and use a straight pointer, but WebPrivatePtr's set of
assign() overloads lead to ambiguity / failure to resolve.

Not normalizing the template argument types wrt 'const' is one issue for
WebPrivatePtr<T>, but the harder ambiguity problem is how to support the
transition type RawPtr<T> (and its implicit conversions) alongside 'bare'
pointers.

Hence opting for RawPtr<WebCore::Notification> here for the time being.

+    WebNotification& operator=(const WTF::RawPtr<WebCore::Notification>&);
 #endif
 
 private: