refactor/rename: fix crash when renaming type embedded in another package.

Fixes golang/go#12038.

Change-Id: I9026edef7f8769b451f2b1502c107d6b2bb45096
Reviewed-on: https://go-review.googlesource.com/13451
Reviewed-by: Alan Donovan <adonovan@google.com>
2 files changed