Revert of Add gpu implementation of SkAvoidXfermode

Revert of Add gpu implementation of SkAvoidXfermode (patchset #10 id:170001 of https://codereview.chromium.org/1658623002/ )

Reason for revert:
shader compilation failures

error C1008: undefined variable "null"

https://uberchromegw.corp.google.com/i/client.skia/builders/Test-Ubuntu-GCC-ShuttleA-GPU-GTX660-x86_64-Debug/builds/4064/steps/dm/logs/stdio

Original issue's description:
> Add gpu implementation of SkAvoidXfermode
> GOLD_TRYBOT_URL= https://gold.skia.org/search2?unt=true&query=source_type%3Dgm&master=false&issue=1658623002
> 
> TBR=bsalomon@google.com
> 
> Committed: https://skia.googlesource.com/skia/+/15691a055db9b68c9b48f589e48d8a85888cf83f

TBR=egdaniel@google.com,bsalomon@google.com,robertphillips@google.com
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true

Committed: https://skia.googlesource.com/skia/+/f16e2a2e92df1eabd04e9e1260ef0b763ecfa426

[mtklein, 2016-02-03 14:42:03]

Created Revert of Add gpu implementation of SkAvoidXfermode

[commit-bot: I haz the power, 2016-02-03 14:42:10]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1663093002/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1663093002/1

[commit-bot: I haz the power, 2016-02-03 14:42:17]

Description was changed from

==========
Revert of Add gpu implementation of SkAvoidXfermode (patchset #10 id:170001 of
https://codereview.chromium.org/1658623002/ )

Reason for revert:
shader compilation failures

error C1008: undefined variable "null"

https://uberchromegw.corp.google.com/i/client.skia/builders/Test-Ubuntu-GCC-S...

Original issue's description:
> Add gpu implementation of SkAvoidXfermode
> GOLD_TRYBOT_URL=
https://gold.skia.org/search2?unt=true&query=source_type%3Dgm&master=false&is...
> 
> TBR=bsalomon@google.com
> 
> Committed:
https://skia.googlesource.com/skia/+/15691a055db9b68c9b48f589e48d8a85888cf83f

TBR=egdaniel@google.com,bsalomon@google.com,robertphillips@google.com
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
==========

to

==========
Revert of Add gpu implementation of SkAvoidXfermode (patchset #10 id:170001 of
https://codereview.chromium.org/1658623002/ )

Reason for revert:
shader compilation failures

error C1008: undefined variable "null"

https://uberchromegw.corp.google.com/i/client.skia/builders/Test-Ubuntu-GCC-S...

Original issue's description:
> Add gpu implementation of SkAvoidXfermode
> GOLD_TRYBOT_URL=
https://gold.skia.org/search2?unt=true&query=source_type%3Dgm&master=false&is...
> 
> TBR=bsalomon@google.com
> 
> Committed:
https://skia.googlesource.com/skia/+/15691a055db9b68c9b48f589e48d8a85888cf83f

TBR=egdaniel@google.com,bsalomon@google.com,robertphillips@google.com
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true

Committed:
https://skia.googlesource.com/skia/+/f16e2a2e92df1eabd04e9e1260ef0b763ecfa426
==========

[commit-bot: I haz the power, 2016-02-03 14:42:18]

Committed patchset #1 (id:1) as
https://skia.googlesource.com/skia/+/f16e2a2e92df1eabd04e9e1260ef0b763ecfa426