Bug 1543001 - ContentBlocking exception should cover top-level domain too, r=Ehsan

Differential Revision: https://phabricator.services.mozilla.com/D26732

--HG--
extra : moz-landing-system : lando

toolkit/components/antitracking/AntiTrackingCommon.cpp

@@ -376,25 +376,42 @@ bool CheckContentBlockingAllowList(nsIHttpChannel* aChannel) {
     return entry.Data().mResult;
   }
 
-  nsCOMPtr<nsIHttpChannelInternal> chan = do_QueryInterface(aChannel);
-  if (chan) {
-    nsCOMPtr<nsIURI> topWinURI;
-    nsresult rv = chan->GetTopWindowURI(getter_AddRefs(topWinURI));
-    if (NS_SUCCEEDED(rv)) {
-      const bool result = CheckContentBlockingAllowList(
-          topWinURI, NS_UsePrivateBrowsing(aChannel));
+  nsCOMPtr<nsILoadInfo> loadInfo = aChannel->LoadInfo();
+  nsContentPolicyType contentPolicyType =
+      loadInfo->GetExternalContentPolicyType();
 
-      entry.Set(ContentBlockingAllowListEntry(aChannel, result));
+  nsCOMPtr<nsIURI> uri;
 
-      return result;
+  // This is the top-level request. Let's use the channel URI.
+  if (contentPolicyType == nsIContentPolicy::TYPE_DOCUMENT) {
+    nsresult rv = NS_GetFinalChannelURI(aChannel, getter_AddRefs(uri));
+    if (NS_WARN_IF(NS_FAILED(rv)) || !uri) {
+      LOG(
+          ("Could not check the content blocking allow list because the "
+           "channel URI is not accessible"));
+      entry.Set(ContentBlockingAllowListEntry(aChannel, false));
+      return false;
+    }
+  } else {
+    nsCOMPtr<nsIHttpChannelInternal> chan = do_QueryInterface(aChannel);
+    MOZ_ASSERT(chan);
+
+    nsresult rv = chan->GetTopWindowURI(getter_AddRefs(uri));
+    if (NS_WARN_IF(NS_FAILED(rv)) || !uri) {
+      LOG(
+          ("Could not check the content blocking allow list because the top "
+           "window wasn't accessible"));
+      entry.Set(ContentBlockingAllowListEntry(aChannel, false));
+      return false;
     }
   }
 
-  LOG(
-      ("Could not check the content blocking allow list because the top "
-       "window wasn't accessible"));
-  entry.Set(ContentBlockingAllowListEntry(aChannel, false));
-  return false;
+  MOZ_ASSERT(uri);
+
+  const bool result =
+      CheckContentBlockingAllowList(uri, NS_UsePrivateBrowsing(aChannel));
+  entry.Set(ContentBlockingAllowListEntry(aChannel, result));
+  return result;
 }
 
 void ReportBlockingToConsole(nsPIDOMWindowOuter* aWindow, nsIURI* aURI,