cc: Fix invalidation problems in impl-side painting

cc: Fix invalidation problems in impl-side painting

The PictureLayerTiling iterator used to stop when it hit a null tile
rather than iterating through null tiles.  So, some invalidations were
ignored because the iterator would hit a null tile from a previous
invalidation rect on the same frame and abort.

This is fixed by making the PictureLayerTiling iterator walk over all i,
j pairs, regardless of whether there is a tile there or not.  The
PictureLayerTilingSet iteration is also made robust to this possibility.

R=nduca@chromium.org
BUG=165246, 165336
Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=172519

[nduca, 2012-12-11 23:13:47]

lgtm

[commit-bot: I haz the power, 2012-12-11 23:25:20]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/enne@chromium.org/11555002/1

[commit-bot: I haz the power, 2012-12-12 02:35:24]

Retried try job too often on linux_chromeos for step(s) browser_tests

[commit-bot: I haz the power, 2012-12-12 03:20:33]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/enne@chromium.org/11555002/1

[commit-bot: I haz the power, 2012-12-12 04:06:12]

Change committed as 172519