Fix point count computation in tessellating path renderer.

Fix point count computation in tessellating path renderer.

The conic, quadratic and cubic computations were using tolerance^2
instead of tolerance when computing maximum point count, causing paths
to be undertessellated when magnifying and overtessellated when minifying.

(Funny story: this bug went unnoticed back when we were tessellating
paths in screen space, when tolerance and its square were both 1.)

BUG=skia:3731
Committed: https://skia.googlesource.com/skia/+/6d88bdb6f1408ec9861ee1306a026e15c5bacc9c

[Stephen White, 2015-04-18 14:39:42]

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

[Stephen White, 2015-04-18 14:39:43]

Rob: PTAL. Thanks!

[Stephen White, 2015-04-20 12:20:47]

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

[commit-bot: I haz the power, 2015-04-20 12:20:56]

Dry run: CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1095773003/1

[commit-bot: I haz the power, 2015-04-20 12:34:58]

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

[commit-bot: I haz the power, 2015-04-20 12:34:59]

Dry run: This issue passed the CQ dry run.

[robertphillips, 2015-04-20 12:41:21]

lgtm

[robertphillips, 2015-04-20 12:41:31]

The CQ bit was checked by robertphillips@google.com

[commit-bot: I haz the power, 2015-04-20 12:41:37]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1095773003/1

[commit-bot: I haz the power, 2015-04-20 12:41:51]

Committed patchset #1 (id:1) as
https://skia.googlesource.com/skia/+/6d88bdb6f1408ec9861ee1306a026e15c5bacc9c

[reed1, 2015-04-20 13:30:44]

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

[reed1, 2015-04-20 13:30:44]

do we expect any layouttest failures/rebaselines?

[Stephen White, 2015-04-20 14:07:34]

On 2015/04/20 13:30:44, reed1 wrote:
> do we expect any layouttest failures/rebaselines?

In Skia, yes. I'll attach the list shortly.

In Blink, no, because MSAA is not enabled.

[reed1, 2015-04-20 14:11:46]

Ah, good (chrome)

No need for a list, as gold will take care of that :)