drm_hwcomposer: Split DrmDisplayCompositor::SquashAll()

Split the SquashAll function into SquashAll and SquashFrame. This
will allow us to squash arbitrary compositions without using the
active composition or applying it to the screen.

Bug: 25379136
Test: Tested on smaug

Change-Id: I1767f731e14f36540151556ce07373848b604030
Signed-off-by: Sean Paul <seanpaul@chromium.org>
2 files changed