All open assets close when referenced item deleted

If you delete an asset that is referenced by another asset, all your current open asset windows (ie. blueprints, animations, meshes, etc.) will close, even if they aren't referencing that asset.

1. Open any project in UE 4.10.4 that has multiple assets (but full Starter Content not needed)
2. Open various Blueprint, Animation, static mesh editor windows that are not related
3. Delete an asset that will prompt you to replace the asset as it is being referenced in the game (but not by any of the opened windows)
   RESULT: All open windows will close regardless of whether they reference the deleted asset or not
   EXPECTED: Opened windows to remain open/unaffected by deleted asset