Remove old puller code from uid sandboxing

Uid sandboxing has been enabled for months now. Remove the old code that
ran before we flipped the flag.

Test: atest statsd_test
Bug: 152544281
Change-Id: Ib7cb79f368ef112774a278a2cf57fffc907a1099
Merged-In: Ib7cb79f368ef112774a278a2cf57fffc907a1099
(cherry picked from commit 75ad6c10)