Bug 821573 - Stop allowing COWs as native interfaces. r=gabor

js/xpconnect/src/XPCConvert.cpp

@@ -908,17 +908,6 @@ XPCConvert::JSObject2NativeInterface(void** dest, HandleObject src,
         // around a security wrapper. XBL does this with Xrays from the XBL
         // scope - see nsBindingManager::GetBindingImplementation.
         JSObject* inner = js::CheckedUnwrap(src, /* stopAtOuter = */ false);
-
-        // Hack - For historical reasons, wrapped chrome JS objects have been
-        // passable as native interfaces. We'd like to fix this, but it
-        // involves fixing the contacts API and PeerConnection to stop using
-        // COWs. This needs to happen, but for now just preserve the old
-        // behavior.
-        //
-        // Note that there is an identical hack in getWrapper which should be
-        // removed if this one is.
-        if (!inner && MOZ_UNLIKELY(xpc::WrapperFactory::IsCOW(src)))
-            inner = js::UncheckedUnwrap(src);
         if (!inner) {
             if (pErr)
                 *pErr = NS_ERROR_XPC_SECURITY_MANAGER_VETO;

js/xpconnect/src/XPCQuickStubs.cpp

@@ -521,18 +521,6 @@ getWrapper(JSContext *cx,
     if (js::IsWrapper(obj)) {
         JSObject* inner = js::CheckedUnwrap(obj, /* stopAtOuter = */ false);
 
-        // Hack - For historical reasons, wrapped chrome JS objects have been
-        // passable as native interfaces. We'd like to fix this, but it
-        // involves fixing the contacts API and PeerConnection to stop using
-        // COWs. This needs to happen, but for now just preserve the old
-        // behavior.
-        //
-        // Note that there is an identical hack in
-        // XPCConvert::JSObject2NativeInterface which should be removed if this
-        // one is.
-        if (!inner && MOZ_UNLIKELY(xpc::WrapperFactory::IsCOW(obj)))
-            inner = js::UncheckedUnwrap(obj);
-
         // The safe unwrap might have failed if we encountered an object that
         // we're not allowed to unwrap. If it didn't fail though, we should be
         // done with wrappers.