Bug 1355680 - set progressMax to -1 when HTTP response head is not available. r=dragana,mayhemer

MozReview-Commit-ID: 6xJsYFlCptC

--HG--
extra : rebase_source : eb11c29314190d29b0b8cdcdeb6841b1cd13a168

netwerk/protocol/http/HttpChannelChild.cpp

@@ -756,7 +756,11 @@ HttpChannelChild::OnTransportAndData(const nsresult& channelStatus,
   // necko msg in between them.
   AutoEventEnqueuer ensureSerialDispatch(mEventQ);
 
-  const int64_t progressMax = mResponseHead->ContentLength();
+  int64_t progressMax;
+  if (NS_FAILED(GetContentLength(&progressMax))) {
+    progressMax = -1;
+  }
+
   const int64_t progress = offset + count;
 
   // OnTransportAndData will be run on retargeted thread if applicable, however