tree 8b5be4e85cc1d7b8241703a08a04698e9505ea45
parent 81d9304bdae3a9282572fd361accfdb034651b45
author Chris Craik <ccraik@google.com> 1411435059 -0700
committer Chris Craik <ccraik@google.com> 1411435320 +0000

Reject transparent draws more conservatively

bug:17600162

Transparent draws are not safe to reject for all xfermodes other than
clear. Now, to be safe, only perform the rejection for SrcOver draws
since other modes are fairly uncommon.

We could specifically determine whether the xfermode could change the
output given a transparent input, but there's little to be gained from
the additional complexity.

Change-Id: Ia699ac4bdc4da3353955840b53f1922d3cb1d85d