Reduce overdraw in MultiPictureDraw Sierpinski GM

Reduce overdraw in MultiPictureDraw Sierpinski GM

As written, all the layers in the MPD Sierpinski GM are full screen. This CL bounds each layer to reduce overdraw.

This CL will cause differences in:

multipicturedraw_sierpinski_simple
multipicturedraw_sierpinski_tiled

but they are/will be suppressed in: (Don't turn on dither for saveLayers which have no paint - https://codereview.chromium.org/619363002/)

Committed: https://skia.googlesource.com/skia/+/7f1ed835e90027f63fbb25d19fb71d128b13834d

[robertphillips, 2014-09-19 21:31:31]

robertphillips@google.com changed reviewers:
+ bsalomon@google.com

[bsalomon, 2014-09-22 14:25:36]

On 2014/09/19 21:32:01, robertphillips wrote:

why does this fix the bug?

[robertphillips, 2014-10-03 12:35:29]

PTAL. (Don't turn on dither for saveLayers which have no paint -
https://codereview.chromium.org/619363002/) fixes the bug but I would still like
to land this cleanup.

[bsalomon, 2014-10-03 13:25:43]

lgtm

[robertphillips, 2014-10-03 13:53:28]

The CQ bit was checked by robertphillips@google.com

[commit-bot: I haz the power, 2014-10-03 13:54:19]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/582633003/20001

[commit-bot: I haz the power, 2014-10-03 14:29:26]

Committed patchset #2 (id:20001) as 7f1ed835e90027f63fbb25d19fb71d128b13834d