Disable advance blend equations.

Disable advance blend equations.

This is a temporary disabling of advanced blend equations till we can fix
the various bugs associated with it.

BUG=skia:3822
Committed: https://skia.googlesource.com/skia/+/28eee1aa2e8e25a52a77ac89d2204738e120c17a

[egdaniel, 2015-05-08 21:35:05]

egdaniel@google.com changed reviewers:
+ bsalomon@google.com

[egdaniel, 2015-05-08 21:35:06]

In our gm's we have been seeing a bunch of blending bugs that occurred after
turning on advance blend equations. There also may be bugs that have been seen
in chrome related to this. So until we can iron these issues out we should
disable it.

[egdaniel, 2015-05-08 21:35:15]

The CQ bit was checked by egdaniel@google.com

[commit-bot: I haz the power, 2015-05-08 21:36:03]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1130003003/1

[commit-bot: I haz the power, 2015-05-08 21:36:23]

Note for Reviewers:
The CQ is waiting for an approval.
If you believe that the CL is not ready yet, or if you would like to L-G-T-M
with comments then please uncheck the CQ checkbox.

Waiting for LGTM from valid reviewer(s) till 2015-05-09 03:36 UTC

[bsalomon, 2015-05-08 21:39:02]

lgtm

[commit-bot: I haz the power, 2015-05-08 21:42:50]

Committed patchset #1 (id:1) as
https://skia.googlesource.com/skia/+/28eee1aa2e8e25a52a77ac89d2204738e120c17a