Merge initHiddenAPI and hiddenAPIUpdatePaths

These two methods did very similar jobs and merging them together
simplifies the behavior.

Bug: 179354495
Test: m droid
Merged-In: Ibe1a23d54105e6a0e5693079cd8743679301fc85
Change-Id: Ibe1a23d54105e6a0e5693079cd8743679301fc85
(cherry picked from commit 74d18d1d)