Bug 1477989 part 2 - Use JS::GetNonCCWObjectGlobal in nsXBLBinding::DoInitJSClass. r=bz

dom/xbl/nsXBLBinding.cpp

@@ -958,7 +958,7 @@ nsXBLBinding::DoInitJSClass(JSContext *cx,
   // and defining it as a property on the XBL scope's global. This works fine,
   // but we need to make sure never to assume that the the reflector and
   // prototype are same-compartment with the bound document.
-  JS::Rooted<JSObject*> global(cx, js::GetGlobalForObjectCrossCompartment(obj));
+  JS::Rooted<JSObject*> global(cx, JS::GetNonCCWObjectGlobal(obj));
 
   // We never store class objects in add-on scopes.
   JS::Rooted<JSObject*> xblScope(cx, xpc::GetXBLScopeOrGlobal(cx, global));

dom/xbl/nsXBLProtoImpl.cpp

@@ -218,6 +218,10 @@ nsXBLProtoImpl::InitTargetObjects(nsXBLPrototypeBinding* aBinding,
   JS::Rooted<JSObject*> value(cx, &v.toObject());
   JSAutoRealm ar2(cx, value);
 
+  // We passed aAllowWrapping = false to nsContentUtils::WrapNative so we
+  // should not have a wrapper.
+  MOZ_ASSERT(!js::IsWrapper(value));
+
   // All of the above code was just obtaining the bound element's script object and its immediate
   // concrete base class.  We need to alter the object so that our concrete class is interposed
   // between the object and its base class.  We become the new base class of the object, and the