Remove __ANDROID_API__ #if checks.

__INTRODUCED_IN() does the right thing automatically now.

Bug: http://b/178449269
Test: treehugger
Change-Id: I94d2ad6fafb6d907793a416db82a9e56f4f61d1c
Merged-In: I94d2ad6fafb6d907793a416db82a9e56f4f61d1c
18 files changed