[Downloads location] Temp fix for surplus offline pages notifications.

There were surplus offline pages notifications (unintended prefetch
notifications and double offline pages notifications) because of a
doubled pathway when OfflineContentAggregatorNotificationBridgeUi is
activated. Temporarily disable OCANBUi for offline pages until a more
long-term fix is in place that can filter out notifications.

Bug: 831083,832282
Change-Id: I49095de6cb9138c2081147342fa76aab9fc8c857
Reviewed-on: https://chromium-review.googlesource.com/1011227
Commit-Queue: Joy Ming <jming@chromium.org>
Reviewed-by: Shakti Sahu <shaktisahu@chromium.org>
Cr-Commit-Position: refs/heads/master@{#550428}
1 file changed