Bug 1453339. Make it harder to mess up Promise::All. r=peterv

MozReview-Commit-ID: UO4wssYHj7

dom/base/nsFrameLoader.cpp

@@ -395,8 +395,6 @@ nsFrameLoader::FireWillChangeProcessEvent()
     return nullptr;
   }
   JSContext* cx = jsapi.cx();
-  GlobalObject global(cx, mOwnerContent->GetOwnerGlobal()->GetGlobalJSObject());
-  MOZ_ASSERT(!global.Failed());
 
   // Set our mBrowserChangingProcessBlockers property to refer to the blockers
   // list. We will synchronously dispatch a DOM event to collect this list of
@@ -418,7 +416,7 @@ nsFrameLoader::FireWillChangeProcessEvent()
   mBrowserChangingProcessBlockers = nullptr;
 
   ErrorResult rv;
-  RefPtr<Promise> allPromise = Promise::All(global, blockers, rv);
+  RefPtr<Promise> allPromise = Promise::All(cx, blockers, rv);
   return allPromise.forget();
 }
 

dom/cache/Cache.cpp

@@ -630,7 +630,7 @@ Cache::AddAll(const GlobalObject& aGlobal,
     new FetchHandler(mActor->GetWorkerHolder(), this,
                      Move(aRequestList), promise);
 
-  RefPtr<Promise> fetchPromise = Promise::All(aGlobal, fetchList, aRv);
+  RefPtr<Promise> fetchPromise = Promise::All(aGlobal.Context(), fetchList, aRv);
   if (NS_WARN_IF(aRv.Failed())) {
     return nullptr;
   }

dom/promise/Promise.cpp

@@ -135,37 +135,40 @@ Promise::Reject(nsIGlobalObject* aGlobal, JSContext* aCx,
 
 // static
 already_AddRefed<Promise>
-Promise::All(const GlobalObject& aGlobal,
+Promise::All(JSContext* aCx,
              const nsTArray<RefPtr<Promise>>& aPromiseList, ErrorResult& aRv)
 {
-  nsCOMPtr<nsIGlobalObject> global;
+  JS::Rooted<JSObject*> globalObj(aCx, JS::CurrentGlobalOrNull(aCx));
-  global = do_QueryInterface(aGlobal.GetAsSupports());
+  if (!globalObj) {
+    aRv.Throw(NS_ERROR_UNEXPECTED);
+    return nullptr;
+  }
+
+  nsCOMPtr<nsIGlobalObject> global = xpc::NativeGlobal(globalObj);
   if (!global) {
     aRv.Throw(NS_ERROR_UNEXPECTED);
     return nullptr;
   }
 
-  JSContext* cx = aGlobal.Context();
+  JS::AutoObjectVector promises(aCx);
-
-  JS::AutoObjectVector promises(cx);
   if (!promises.reserve(aPromiseList.Length())) {
-    aRv.NoteJSContextException(cx);
+    aRv.NoteJSContextException(aCx);
     return nullptr;
   }
 
   for (auto& promise : aPromiseList) {
-    JS::Rooted<JSObject*> promiseObj(cx, promise->PromiseObj());
+    JS::Rooted<JSObject*> promiseObj(aCx, promise->PromiseObj());
     // Just in case, make sure these are all in the context compartment.
-    if (!JS_WrapObject(cx, &promiseObj)) {
+    if (!JS_WrapObject(aCx, &promiseObj)) {
-      aRv.NoteJSContextException(cx);
+      aRv.NoteJSContextException(aCx);
       return nullptr;
     }
     promises.infallibleAppend(promiseObj);
   }
 
-  JS::Rooted<JSObject*> result(cx, JS::GetWaitForAllPromise(cx, promises));
+  JS::Rooted<JSObject*> result(aCx, JS::GetWaitForAllPromise(aCx, promises));
   if (!result) {
-    aRv.NoteJSContextException(cx);
+    aRv.NoteJSContextException(aCx);
     return nullptr;
   }
 

dom/promise/Promise.h

@@ -111,23 +111,26 @@ public:
     return mGlobal;
   }
 
-  // Do the equivalent of Promise.resolve in the current compartment of aCx.
+  // Do the equivalent of Promise.resolve in the compartment of aGlobal.  The
-  // Errorrs are reported on the ErrorResult; if aRv comes back !Failed(), this
+  // compartment of aCx is ignored.  Errors are reported on the ErrorResult; if
-  // function MUST return a non-null value.
+  // aRv comes back !Failed(), this function MUST return a non-null value.
   static already_AddRefed<Promise>
   Resolve(nsIGlobalObject* aGlobal, JSContext* aCx,
           JS::Handle<JS::Value> aValue, ErrorResult& aRv);
 
-  // Do the equivalent of Promise.reject in the current compartment of aCx.
+  // Do the equivalent of Promise.reject in the compartment of aGlobal.  The
-  // Errorrs are reported on the ErrorResult; if aRv comes back !Failed(), this
+  // compartment of aCx is ignored.  Errors are reported on the ErrorResult; if
-  // function MUST return a non-null value.
+  // aRv comes back !Failed(), this function MUST return a non-null value.
   static already_AddRefed<Promise>
   Reject(nsIGlobalObject* aGlobal, JSContext* aCx,
          JS::Handle<JS::Value> aValue, ErrorResult& aRv);
 
+  // Do the equivalent of Promise.all in the current compartment of aCx.  Errors
+  // are reported on the ErrorResult; if aRv comes back !Failed(), this function
+  // MUST return a non-null value.
   static already_AddRefed<Promise>
-  All(const GlobalObject& aGlobal,
+  All(JSContext* aCx, const nsTArray<RefPtr<Promise>>& aPromiseList,
-      const nsTArray<RefPtr<Promise>>& aPromiseList, ErrorResult& aRv);
+      ErrorResult& aRv);
 
   void
   Then(JSContext* aCx,

layout/style/FontFaceSet.cpp

@@ -346,17 +346,7 @@ FontFaceSet::Load(JSContext* aCx,
     }
   }
 
-  nsIGlobalObject* globalObject = GetParentObject();
+  return Promise::All(aCx, promises, aRv);
-  if (!globalObject) {
-    aRv.Throw(NS_ERROR_FAILURE);
-    return nullptr;
-  }
-
-  JS::Rooted<JSObject*> jsGlobal(aCx, globalObject->GetGlobalJSObject());
-  GlobalObject global(aCx, jsGlobal);
-
-  RefPtr<Promise> result = Promise::All(global, promises, aRv);
-  return result.forget();
 }
 
 bool