Add an option to rebaseline.py to mark tests as ignore-failure.

Add an option to rebaseline.py to mark tests as ignore-failure.

R=epoger@google.com, epoger

Committed: https://code.google.com/p/skia/source/detail?r=11358

[Stephen White, 2013-09-18 19:05:00]

PTAL: this is a WIP, but maybe you can help me nudge it in the right direction.

Known issues: this only marks tests as ignore-failure if they're currently
failing on the bots, so it's not too useful for pre-emptively marking a test as
expected-to-fail when landing code changes. Also needs a test.

[epoger, 2013-09-18 19:13:11]

LGTM!  Thanks for doing this... somehow I thought I had already added that flag,
but nope.

On 2013/09/18 19:05:00, Stephen White wrote:
> PTAL: this is a WIP, but maybe you can help me nudge it in the right
direction.
> 
> Known issues: this only marks tests as ignore-failure if they're currently
> failing on the bots, so it's not too useful for pre-emptively marking a test
as
> expected-to-fail when landing code changes. 

Right.  This change addresses part 1 of
https://code.google.com/p/skia/issues/detail?id=1600#c2 , but not part 2.

[Stephen White, 2013-09-18 19:14:49]

Committed patchset #1 manually as r11358 (presubmit successful).