Revert "Remove AHardwareBuffer_ API from libandroid"

This reverts commit 8e90cc3e.

Both ANativeWindow and AHardwareBuffer need to be
available in libandroid (as well as libnativewindow)
otherwise it would make our developer’s life
very difficult when they want to support multiple
versions of android.

Moreover, this would have an impact on AndroidStudio
when doing an NDK project.

Test: compiled
Bug: treble

Change-Id: I2cc63b06b3f80fa80f7170ba2ba2996228fa9b2c