Merge branch 'jk/loose-object-info-report-error'

Update error handling for codepath that deals with corrupt loose
objects.

* jk/loose-object-info-report-error:
  index-pack: detect local corruption in collision check
  sha1_loose_object_info: return error for corrupted objects

diff --cc builtin/index-pack.c
Simple merge

diff --cc sha1_file.c
Simple merge