Treat (private, internal) grid bounds as doubly-inclusive in SkTileGrid.

Treat (private, internal) grid bounds as doubly-inclusive in SkTileGrid.

The net effect is that two "+1" instructions are removed from insert().
search() nets no change: two +1 removed, two +1 added.

When vectorized, this removes the need to add in userToGrid() at all and
so the need to read an awkward {0, 0, 1, 1} constant from memory.  Mostly
the benefit is less vector code to look at and think about.

BUG=skia:

Committed: https://skia.googlesource.com/skia/+/826a50333612e81d1de87a58e32e4f9a3baddefd

[mtklein, 2014-10-15 21:12:21]

mtklein@google.com changed reviewers:
+ mtklein@google.com, reed@google.com

[mtklein, 2014-10-15 21:12:21]

Since you asked...

[mtklein, 2014-10-15 21:12:25]

The CQ bit was checked by mtklein@google.com

[commit-bot: I haz the power, 2014-10-15 21:13:18]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/659823004/1

[commit-bot: I haz the power, 2014-10-15 21:13:19]

Note for Reviewers:
The CQ is waiting for an approval.
If you believe that the CL is not ready yet, or if you would like to L-G-T-M
with comments then please uncheck the CQ checkbox.

Waiting for LGTM from valid reviewer(s) till 2014-10-16 03:13 UTC

[reed1, 2014-10-15 21:18:55]

lgtm

[commit-bot: I haz the power, 2014-10-15 21:20:05]

Committed patchset #1 (id:1) as 826a50333612e81d1de87a58e32e4f9a3baddefd