Fix missing break when parsing allow-package-shareduid

Not using a flag because the fix can't be more straightforward, trivial
and safe.

Bug: 348301951
Flag: EXEMPT bugfix
Test: presubmit
(cherry picked from https://googleplex-android-review.googlesource.com/q/commit:77ee45f3de234fd816a576023534e9cb90cca04b)
Merged-In: I7903d300c70514027df783b614fbe816df989654
Change-Id: I7903d300c70514027df783b614fbe816df989654