Always use a color table with 256 colors

Always use a color table with 256 colors

Speculative fix for skbug.com/5883

We are hitting an assert (which I have not been able to repro - still
need to get the skp that triggers it) because we are trying to read
beyond the end of the color table. We use 8-bit indices, so 256 should
be enough to prevent going beyond the end. There is only one case when
we use a smaller color table - when it is a dummy. Make the dummy full
size.

NOTREECHECKS=true

BUG=skia:5883
GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2452673002

Committed: https://skia.googlesource.com/skia/+/0057ac11fccc82bc5b0c1bb0aefe838cc04efd13

[scroggo_chromium, 2016-10-25 16:02:55]

Description was changed from

==========
Always use a color table with 256 colors

Speculative fix for skbug.com/5883

We are hitting an assert (which I have not been able to repro - still
need to get the skp that triggers it) because we are trying to read
beyond the end of the color table. We use 8-bit indices, so 256 should
be enough to prevent going beyond the end. There is only one case when
we use a smaller color table - when it is a dummy. Make the dummy full
size.

BUG=skia:5883
==========

to

==========
Always use a color table with 256 colors

Speculative fix for skbug.com/5883

We are hitting an assert (which I have not been able to repro - still
need to get the skp that triggers it) because we are trying to read
beyond the end of the color table. We use 8-bit indices, so 256 should
be enough to prevent going beyond the end. There is only one case when
we use a smaller color table - when it is a dummy. Make the dummy full
size.

BUG=skia:5883
GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2452673002
==========

[scroggo_chromium, 2016-10-25 16:03:24]

scroggo@chromium.org changed reviewers:
+ msarett@google.com

[msarett, 2016-10-25 17:02:49]

lgtm

I assume that the plan is to eventually track down the skp and understand why
this is happening?

[scroggo_chromium, 2016-10-25 18:00:37]

The CQ bit was checked by scroggo@chromium.org

[commit-bot: I haz the power, 2016-10-25 18:00:41]

CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[scroggo_chromium, 2016-10-25 19:31:23]

On 2016/10/25 17:02:49, msarett wrote:
> lgtm
> 
> I assume that the plan is to eventually track down the skp and understand why
> this is happening?

Yes. I've uploaded a better fix at https://codereview.chromium.org/2450943002
(but I still think it's fine to land this for now).

[scroggo_chromium, 2016-10-25 19:41:23]

Description was changed from

==========
Always use a color table with 256 colors

Speculative fix for skbug.com/5883

We are hitting an assert (which I have not been able to repro - still
need to get the skp that triggers it) because we are trying to read
beyond the end of the color table. We use 8-bit indices, so 256 should
be enough to prevent going beyond the end. There is only one case when
we use a smaller color table - when it is a dummy. Make the dummy full
size.

BUG=skia:5883
GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2452673002
==========

to

==========
Always use a color table with 256 colors

Speculative fix for skbug.com/5883

We are hitting an assert (which I have not been able to repro - still
need to get the skp that triggers it) because we are trying to read
beyond the end of the color table. We use 8-bit indices, so 256 should
be enough to prevent going beyond the end. There is only one case when
we use a smaller color table - when it is a dummy. Make the dummy full
size.

NOTREECHECKS=true

BUG=skia:5883
GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2452673002
==========

[scroggo_chromium, 2016-10-25 19:42:32]

The CQ bit was unchecked by scroggo@chromium.org

[scroggo_chromium, 2016-10-25 19:42:32]

The CQ bit was checked by scroggo@chromium.org

[commit-bot: I haz the power, 2016-10-25 19:42:43]

CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[commit-bot: I haz the power, 2016-10-25 19:48:27]

Description was changed from

==========
Always use a color table with 256 colors

Speculative fix for skbug.com/5883

We are hitting an assert (which I have not been able to repro - still
need to get the skp that triggers it) because we are trying to read
beyond the end of the color table. We use 8-bit indices, so 256 should
be enough to prevent going beyond the end. There is only one case when
we use a smaller color table - when it is a dummy. Make the dummy full
size.

NOTREECHECKS=true

BUG=skia:5883
GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2452673002
==========

to

==========
Always use a color table with 256 colors

Speculative fix for skbug.com/5883

We are hitting an assert (which I have not been able to repro - still
need to get the skp that triggers it) because we are trying to read
beyond the end of the color table. We use 8-bit indices, so 256 should
be enough to prevent going beyond the end. There is only one case when
we use a smaller color table - when it is a dummy. Make the dummy full
size.

NOTREECHECKS=true

BUG=skia:5883
GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2452673002

Committed:
https://skia.googlesource.com/skia/+/0057ac11fccc82bc5b0c1bb0aefe838cc04efd13
==========

[commit-bot: I haz the power, 2016-10-25 19:48:28]

Committed patchset #1 (id:1) as
https://skia.googlesource.com/skia/+/0057ac11fccc82bc5b0c1bb0aefe838cc04efd13