Check for duplicate bundled files from different modules.

A single file generated by different modules is almost never correct;
make it an error.

The check is skipped for some error cases, which will be handled in follow-ups.

Bug: 191770320
Test: m (soong test)
Change-Id: Ib3c6efd16bdf13b59f79be66d4f9dba49100f6cc