Add __INTRODUCED_IN to core <android/*.h> APIs.

Bug: https://github.com/android-ndk/ndk/issues/706
Bug: http://b/113052379
Test: builds
Change-Id: I23db5a2180517045bafabe6fbf783456cbddf21a
(cherry picked from commit 9db409b053460e065cefb1d1caefe048f90cfff0)
10 files changed