Bug 1899180. If a channel is not nsIPrivateBrowsingChannel and has no load...

Bug 1899180. If a channel is not nsIPrivateBrowsingChannel and has no load context, use the private browsing field from it's origin attributes. r=necko-reviewers,anti-tracking-reviewers,valentin

If the channel is not a nsIPrivateBrowsingChannel, and it also has no load context (eg inside svg images) then we will over write a non-zero mPrivateBrowsingId on the OriginAttributes of the channel with 0, making NS_UsePrivateBrowsing return false for the channel.

Differential Revision: https://phabricator.services.mozilla.com/D212083

toolkit/components/antitracking/StoragePrincipalHelper.cpp

@@ -445,7 +445,7 @@ bool StoragePrincipalHelper::GetOriginAttributes(
   nsCOMPtr<nsILoadInfo> loadInfo = aChannel->LoadInfo();
   loadInfo->GetOriginAttributes(&aAttributes);
 
-  bool isPrivate = false;
+  bool isPrivate = aAttributes.mPrivateBrowsingId > 0;
   nsCOMPtr<nsIPrivateBrowsingChannel> pbChannel = do_QueryInterface(aChannel);
   if (pbChannel) {
     nsresult rv = pbChannel->GetIsChannelPrivate(&isPrivate);
@@ -454,7 +454,9 @@ bool StoragePrincipalHelper::GetOriginAttributes(
     // Some channels may not implement nsIPrivateBrowsingChannel
     nsCOMPtr<nsILoadContext> loadContext;
     NS_QueryNotificationCallbacks(aChannel, loadContext);
-    isPrivate = loadContext && loadContext->UsePrivateBrowsing();
+    if (loadContext) {
+      isPrivate = loadContext->UsePrivateBrowsing();
+    }
   }
   aAttributes.SyncAttributesWithPrivateBrowsing(isPrivate);