Try out operator overloads for Sk2x.

Try out operator overloads for Sk2x.

BUG=skia:

Committed: https://skia.googlesource.com/skia/+/d800d878caae5d25b275d488a1b5ae8c24cea492

[mtklein_C, 2015-03-19 20:06:32]

mtklein@chromium.org changed reviewers:
+ caryclark@google.com, reed@google.com

[caryclark, 2015-03-19 20:42:32]

I find this much easier to read

lgtm

[mtklein, 2015-03-19 20:44:35]

Forgot to mention, I'll follow up with an analogous change to whatever we land
here for Sk4f.

[reed1, 2015-03-19 21:11:52]

purty lgtm

[mtklein, 2015-03-19 21:13:56]

The CQ bit was checked by mtklein@google.com

[mtklein, 2015-03-19 21:13:56]

The patchset sent to the CQ was uploaded after l-g-t-m from
caryclark@google.com, reed@google.com
Link to the patchset: https://codereview.chromium.org/1024473005/#ps40001
(title: "simpler math")

[commit-bot: I haz the power, 2015-03-19 21:21:28]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1024473005/40001

[commit-bot: I haz the power, 2015-03-19 21:28:41]

Committed patchset #3 (id:40001) as
https://skia.googlesource.com/skia/+/d800d878caae5d25b275d488a1b5ae8c24cea492