Remove SK_SUPPORT_LEGACY_SCALAR_MAPPOINTS

Remove SK_SUPPORT_LEGACY_SCALAR_MAPPOINTS

No longer used in Chromium.

Also drop now-unused SkMatrix::Rot_pts() & SkMatrix::RotTrans_pts().

BUG=475022
R=reed@google.com,mtklein@google.com

Committed: https://skia.googlesource.com/skia/+/f57546ec7f9ab116d80044e19aa5e72060dbff09

[f(malita), 2015-04-09 02:19:21]

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

[commit-bot: I haz the power, 2015-04-09 02:20:07]

Dry run: CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1071833002/1

[commit-bot: I haz the power, 2015-04-09 02:25:40]

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

[commit-bot: I haz the power, 2015-04-09 02:25:41]

This issue passed the CQ dry run.

[mtklein, 2015-04-09 10:12:07]

lgtm

[f(malita), 2015-04-09 12:51:10]

The CQ bit was checked by fmalita@chromium.org

[commit-bot: I haz the power, 2015-04-09 12:51:21]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1071833002/1

[commit-bot: I haz the power, 2015-04-09 12:51:25]

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

[commit-bot: I haz the power, 2015-04-09 12:51:26]

Presubmit check for 1071833002-1 failed and returned exit status 1.

Running presubmit commit checks ...

** Presubmit ERRORS **
Since the CL is editing public API, you must have an LGTM from one of:
('reed@chromium.org', 'reed@google.com', 'bsalomon@chromium.org',
'bsalomon@google.com', 'djsollen@chromium.org', 'djsollen@google.com')

[reed1, 2015-04-09 13:06:20]

lgtm

[mtklein, 2015-04-09 13:12:58]

The CQ bit was checked by mtklein@google.com

[commit-bot: I haz the power, 2015-04-09 13:13:08]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1071833002/1

[commit-bot: I haz the power, 2015-04-09 13:13:19]

Committed patchset #1 (id:1) as
https://skia.googlesource.com/skia/+/f57546ec7f9ab116d80044e19aa5e72060dbff09