Add missing DRAW_PICTURE_MATRIX_PAINT paint offset.

Add missing DRAW_PICTURE_MATRIX_PAINT paint offset.

Also remove explicit gPaintOffsets sizing to make the existing compile
time size check effective.

R=reed@google.com,robertphillips@google.com

Committed: https://skia.googlesource.com/skia/+/9f49cfdbf6493b953775890d7f9c97a1dce0d341

[f(malita), 2014-08-12 17:03:22]

Would be much nicer to move the paint upfront (to avoid relying on SkMatrix
sizeInMemory), but I presume at this point we don't want to break the SKP
format?

[robertphillips, 2014-08-12 17:05:26]

lgtm

[f(malita), 2014-08-12 17:18:16]

On 2014/08/12 17:05:26, robertphillips wrote:
> lgtm

Updated to serialize paint first - PTAL.

[robertphillips, 2014-08-12 17:26:15]

You don't want to move the matrix forward too?

[f(malita), 2014-08-12 17:38:39]

On 2014/08/12 17:26:15, robertphillips wrote:
> You don't want to move the matrix forward too?

I was only concerned with the paint offset, but yeah, we can move the matrix
too. Done.

[robertphillips, 2014-08-12 19:16:01]

lgtm

[f(malita), 2014-08-12 19:18:28]

The CQ bit was checked by fmalita@chromium.org

[commit-bot: I haz the power, 2014-08-12 19:19:25]

CQ is trying da patch. Follow status at
 https://skia-tree-status.appspot.com/cq/fmalita@chromium.org/467683003/40001

[commit-bot: I haz the power, 2014-08-12 19:24:25]

Change committed as 9f49cfdbf6493b953775890d7f9c97a1dce0d341