drm_hwcomposer: Save the atomic_test result between tests

Previously, we would only test the first frame when the geometry
changed. However, if SF sent us the same composition with different
FBs, we could end up sending invalid frames to the kernel.

This change saves the result of the atomic_test between geometry
changes so we avoid using hw composition for all invalid frames.

Bug: 25866352
Test: Tested on smaug, observed squashes between geometry changes

Change-Id: I3b5d9e83a870481bf2e6869900eafaf0ca66a0d5
Signed-off-by: Sean Paul <seanpaul@chromium.org>
(cherry picked from commit 6c18b3b67e50e12f77f76108363493162ff36340)
2 files changed