Take span len into account when determining whether gradient is vertical

Take span len into account when determining whether gradient is vertical

R=reed@google.com

Committed: https://skia.googlesource.com/skia/+/2b46913c99319de9567390e8a543057be0c162e3

[f(malita), 2015-11-23 15:24:52]

The CQ bit was checked by fmalita@chromium.org to run a CQ dry run

[commit-bot: I haz the power, 2015-11-23 15:25:05]

Dry run: CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1471753004/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1471753004/1

[commit-bot: I haz the power, 2015-11-23 15:37:13]

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

[commit-bot: I haz the power, 2015-11-23 15:37:14]

Dry run: This issue passed the CQ dry run.

[reed1, 2015-11-23 16:15:03]

Nice idea. Does this fix a particular test, or speed something up?

lgtm

[f(malita), 2015-11-23 16:29:28]

On 2015/11/23 16:15:03, reed1 wrote:
> Nice idea. Does this fix a particular test, or speed something up?
> 
> lgtm

It prevents a regression i noticed when browsing gradient-related bugs with the
new impl.  No Skia/Blink coverage ATM, maybe we can add a test.

[f(malita), 2015-11-23 16:29:32]

The CQ bit was checked by fmalita@chromium.org

[commit-bot: I haz the power, 2015-11-23 16:29:35]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1471753004/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1471753004/1

[commit-bot: I haz the power, 2015-11-23 16:30:26]

Committed patchset #1 (id:1) as
https://skia.googlesource.com/skia/+/2b46913c99319de9567390e8a543057be0c162e3