Fix replacement-after-add of resource files in overlay.

Aapt was adding/removing elements from a list an continuing to use a stale copy for future indexes.
This could cause incorrect subsequent processing.  Add an en resource and modify an es, for example.
Adding the en would cause the base fileset's es version to be moved in the list.  Using the old index
we'd then attempt to remove the old es version with the wrong index and then add the new es version
generating a "duplicate file" error.

bug: 2090015