GravityCompat.apply tests.

This is for the variant that doesn't get offsets. The tests
exercise all nine possible permutations of core horizontal /
vertical gravity constants, as well as additional six permutations
of two compat horizontal constants (start / end) with core vertical
constants.

Tests are split into two groups - LTR and RTL direction.

Change-Id: Iee287f3cb3173b680ad88779906b8c70a35a43b1
2 files changed