Reland "remove unused SkAvoidXfermode"

Reland "remove unused SkAvoidXfermode"

(patchset #2 id:20001 of https://codereview.chromium.org/860583002/)

SkAvoidXfermode has been moved into Android, so it is safe to remove.

Committed: https://skia.googlesource.com/skia/+/e7ea40f4e0ef9f5405c256432fde87f521a9a2ef

[scroggo, 2015-01-30 13:58:55]

Created Revert of Revert of remove unused SkAvoidXfermode

[scroggo, 2015-01-30 14:00:54]

scroggo@google.com changed reviewers:
+ reed@google.com

[scroggo, 2015-01-30 14:01:20]

Mike, Android no longer needs this, so safe to remove.

[scroggo, 2015-01-30 15:09:11]

The CQ bit was checked by scroggo@google.com

[commit-bot: I haz the power, 2015-01-30 15:10:06]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/890893003/1

[commit-bot: I haz the power, 2015-01-30 15:10:07]

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 2015-01-30 21:10 UTC

[commit-bot: I haz the power, 2015-01-30 21:10:07]

The CQ bit was unchecked by commit-bot@chromium.org

[commit-bot: I haz the power, 2015-01-30 21:10:08]

No LGTM from a valid reviewer yet. Please ask for an LGTM from a
full Skia committer from
https://skia.googlesource.com/skia/+/master/CQ_COMMITTERS

[reed1, 2015-01-30 21:15:37]

lgtm

[reed1, 2015-01-30 21:15:41]

The CQ bit was checked by reed@google.com

[commit-bot: I haz the power, 2015-01-30 21:15:46]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/890893003/1

[commit-bot: I haz the power, 2015-01-30 21:16:06]

Committed patchset #1 (id:1) as
https://skia.googlesource.com/skia/+/e7ea40f4e0ef9f5405c256432fde87f521a9a2ef