Fix bug in ico decodes

Fix bug in ico decodes

Some icos have been looking a bit strange in Gold.

Looks like the cause was that we were decoding to kUnpremul
accidentally.

BUG=skia:

Committed: https://skia.googlesource.com/skia/+/d67d08ed339d6dabe318bf869a4fed6ed91e9a78

[msarett, 2015-09-02 20:35:48]

Patchset #1 (id:1) has been deleted

[msarett, 2015-09-02 20:37:44]

Patchset #1 (id:20001) has been deleted

[msarett, 2015-09-02 20:37:54]

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

[scroggo, 2015-09-02 21:50:54]

lgtm

https://codereview.chromium.org/1321913003/diff/40001/src/codec/SkCodec_libic...
File src/codec/SkCodec_libico.cpp (right):

https://codereview.chromium.org/1321913003/diff/40001/src/codec/SkCodec_libic...
src/codec/SkCodec_libico.cpp:265: embeddedAlpha = dstInfo.alphaType();
I suppose this is safe because dstInfo.alphaType() was already checked above?

[msarett, 2015-09-02 21:56:37]

https://codereview.chromium.org/1321913003/diff/40001/src/codec/SkCodec_libic...
File src/codec/SkCodec_libico.cpp (right):

https://codereview.chromium.org/1321913003/diff/40001/src/codec/SkCodec_libic...
src/codec/SkCodec_libico.cpp:265: embeddedAlpha = dstInfo.alphaType();
On 2015/09/02 21:50:54, scroggo wrote:
> I suppose this is safe because dstInfo.alphaType() was already checked above?

Yes - we always guess that ICOs have alpha (and therefore require dstInfo to
have alpha).  This would need to change if we allow icos to sometimes be opaque.

I don't think we can ever allow bmp-in-icos to be opaque given that they have an
alpha mask.  It's possible/allowable for png-in-icos to be opaque.  Though it
seems rare.

I'm guessing that when I address the FIXME, we will allow opaque png-in-icos and
need to make a slight modification here.

[msarett, 2015-09-02 21:56:44]

The CQ bit was checked by msarett@google.com

[commit-bot: I haz the power, 2015-09-02 21:56:51]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1321913003/40001
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1321913003/40001

[commit-bot: I haz the power, 2015-09-02 21:56:52]

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 2015-09-03 03:56 UTC

[commit-bot: I haz the power, 2015-09-02 23:23:46]

Committed patchset #1 (id:40001) as
https://skia.googlesource.com/skia/+/d67d08ed339d6dabe318bf869a4fed6ed91e9a78