Tesellating path renderer: typecast cleanup; logging build fix.

Tesellating path renderer: typecast cleanup; logging build fix.

Use SkPoint* for all vertex data. (It was void* to support two different
vertex data formats, which we no longer need.)
Assert that vertex stride == sizeof(SkPoint).
Fix build when LOGGING_ENABLED=1.

BUG=skia:

Committed: https://skia.googlesource.com/skia/+/d4d83eb032845b7aefbeeb717bdb3faeba864aa9

[Stephen White, 2015-05-14 15:27:28]

senorblanco@chromium.org changed reviewers:
+ robertphillips@chromium.org

[Stephen White, 2015-05-14 15:27:37]

robertphillips@: PTAL. Thanks!

[Stephen White, 2015-05-14 15:30:21]

The CQ bit was checked by senorblanco@chromium.org to run a CQ dry run

[commit-bot: I haz the power, 2015-05-14 15:30:34]

Dry run: CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1128083004/1

[commit-bot: I haz the power, 2015-05-14 15:40:02]

The CQ bit was unchecked by commit-bot@chromium.org

[commit-bot: I haz the power, 2015-05-14 15:40:03]

Dry run: This issue passed the CQ dry run.

[robertphillips, 2015-05-14 15:46:14]

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

[robertphillips, 2015-05-14 15:46:15]

lgtm

[Stephen White, 2015-05-14 16:07:33]

The CQ bit was checked by senorblanco@chromium.org

[commit-bot: I haz the power, 2015-05-14 16:07:55]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1128083004/1

[commit-bot: I haz the power, 2015-05-14 16:08:20]

Committed patchset #1 (id:1) as
https://skia.googlesource.com/skia/+/d4d83eb032845b7aefbeeb717bdb3faeba864aa9