Bug 904559 - Veto redirect when target channel doesn't implement nsIParentRedirectingChannel. r=jduell

netwerk/protocol/http/HttpChannelParentListener.cpp

@@ -166,6 +166,14 @@ HttpChannelParentListener::AsyncOnChannelRedirect(
 {
   nsresult rv;
 
+  nsCOMPtr<nsIParentRedirectingChannel> activeRedirectingChannel =
+      do_QueryInterface(mNextListener);
+  if (!activeRedirectingChannel) {
+    NS_ERROR("Channel got a redirect response, but doesn't implement "
+             "nsIParentRedirectingChannel to handle it.");
+    return NS_ERROR_NOT_IMPLEMENTED;
+  }
+
   // Register the new channel and obtain id for it
   nsCOMPtr<nsIRedirectChannelRegistrar> registrar =
       do_GetService("@mozilla.org/redirectchannelregistrar;1", &rv);
@@ -176,13 +184,6 @@ HttpChannelParentListener::AsyncOnChannelRedirect(
 
   LOG(("Registered %p channel under id=%d", newChannel, mRedirectChannelId));
 
-  nsCOMPtr<nsIParentRedirectingChannel> activeRedirectingChannel =
-      do_QueryInterface(mNextListener);
-  if (!activeRedirectingChannel) {
-    NS_RUNTIMEABORT("Channel got a redirect response, but doesn't implement "
-                    "nsIParentRedirectingChannel to handle it.");
-  }
-
   return activeRedirectingChannel->StartRedirect(mRedirectChannelId,
                                                  newChannel,
                                                  redirectFlags,