Bug 1492894 - part 2 - eliminate already_AddRefed variables in netwerk/; r=valentin

We need to disallow these to fix our static analysis, which should have
already been disallowing them.

netwerk/base/AutoClose.h

@@ -38,8 +38,7 @@ public:
 
   void takeOver(nsCOMPtr<T> & rhs)
   {
-    already_AddRefed<T> other = rhs.forget();
-    TakeOverInternal(&other);
+    TakeOverInternal(rhs.forget());
   }
 
   void CloseAndRelease()
@@ -48,15 +47,12 @@ public:
   }
 
 private:
-  void TakeOverInternal(already_AddRefed<T> *aOther)
+  void TakeOverInternal(already_AddRefed<T>&& aOther)
   {
-    nsCOMPtr<T> ptr;
+    nsCOMPtr<T> ptr(std::move(aOther));
     {
       MutexAutoLock lock(mMutex);
       ptr.swap(mPtr);
-      if (aOther) {
-        mPtr = *aOther;
-      }
     }
 
     if (ptr) {

netwerk/protocol/http/HttpChannelParent.cpp

@@ -734,10 +734,10 @@ HttpChannelParent::WaitForBgParent()
   registrar->LinkHttpChannel(mChannel->ChannelId(), this);
 
   if (mBgParent) {
-    already_AddRefed<GenericPromise> promise = mPromise.Ensure(__func__);
+    RefPtr<GenericPromise> promise = mPromise.Ensure(__func__);
     // resolve promise immediatedly if bg channel is ready.
     mPromise.Resolve(true, __func__);
-    return promise;
+    return promise.forget();
   }
 
   return mPromise.Ensure(__func__);;