Add VisibleUnits::startOfWordPosition

Add VisibleUnits::startOfWordPosition

This is Position version of |startOfWord| which returns VisiblePosition.
Since returned Position should be already canonicalized with 
|previousBoundary()|, we can replace them.

This is preparation for letting |startOfWord| and |endOfWord| return
 uncanonicalized Position.

BUG=657237, 697725
TEST=No change in behavior.

Review-Url: https://codereview.chromium.org/2732863004
Cr-Commit-Position: refs/heads/master@{#455146}
Committed: https://chromium.googlesource.com/chromium/src/+/f47de6fa1c432e87dc270ff96b1089e5983c2cf1

[yoichio, 2017-03-07 02:13:11]

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

[commit-bot: I haz the power, 2017-03-07 02:14:05]

Dry run: CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[yoichio, 2017-03-07 02:14:55]

Description was changed from

==========
startOfWordPosition

BUG=657237,697725
==========

to

==========
Add VisibleUnits::startOfWordPosition

This is Position version of |startOfWord| which returns VisiblePosition.
Since returned Position should be already canonicalized with 
|previousBoundary()|, we can replace them.

This is preparation for letting |startOfWord| and |endOfWord| return
 uncanonicalized Position.

BUG=657237,697725
TEST=No change in behavior.
==========

[yoichio, 2017-03-07 02:14:55]

yoichio@chromium.org changed reviewers:
+ yosin@chromium.org

[yosin_UTC9, 2017-03-07 02:20:31]

lgtm

[commit-bot: I haz the power, 2017-03-07 05:30:00]

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

[commit-bot: I haz the power, 2017-03-07 05:30:00]

Dry run: Try jobs failed on following builders:
  win_chromium_x64_rel_ng on master.tryserver.chromium.win (JOB_FAILED,
http://build.chromium.org/p/tryserver.chromium.win/builders/win_chromium_x64_...)

[yoichio, 2017-03-07 07:58:16]

The CQ bit was checked by yoichio@chromium.org

[commit-bot: I haz the power, 2017-03-07 07:58:47]

CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[commit-bot: I haz the power, 2017-03-07 09:42:18]

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

[commit-bot: I haz the power, 2017-03-07 09:42:19]

Try jobs failed on following builders:
  win_chromium_x64_rel_ng on master.tryserver.chromium.win (JOB_FAILED,
http://build.chromium.org/p/tryserver.chromium.win/builders/win_chromium_x64_...)

[yoichio, 2017-03-07 14:13:09]

The CQ bit was checked by yoichio@chromium.org

[commit-bot: I haz the power, 2017-03-07 14:13:30]

CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[commit-bot: I haz the power, 2017-03-07 18:28:38]

CQ is committing da patch.

Bot data: {"patchset_id": 1, "attempt_start_ts": 1488895989185180, "parent_rev":
"c3d234f50f3d487796c1c859ca7d5636e2932d91", "commit_rev":
"f47de6fa1c432e87dc270ff96b1089e5983c2cf1"}

[commit-bot: I haz the power, 2017-03-07 18:29:16]

Description was changed from

==========
Add VisibleUnits::startOfWordPosition

This is Position version of |startOfWord| which returns VisiblePosition.
Since returned Position should be already canonicalized with 
|previousBoundary()|, we can replace them.

This is preparation for letting |startOfWord| and |endOfWord| return
 uncanonicalized Position.

BUG=657237,697725
TEST=No change in behavior.
==========

to

==========
Add VisibleUnits::startOfWordPosition

This is Position version of |startOfWord| which returns VisiblePosition.
Since returned Position should be already canonicalized with 
|previousBoundary()|, we can replace them.

This is preparation for letting |startOfWord| and |endOfWord| return
 uncanonicalized Position.

BUG=657237,697725
TEST=No change in behavior.

Review-Url: https://codereview.chromium.org/2732863004
Cr-Commit-Position: refs/heads/master@{#455146}
Committed:
https://chromium.googlesource.com/chromium/src/+/f47de6fa1c432e87dc270ff96b10...
==========

[commit-bot: I haz the power, 2017-03-07 18:29:18]

Committed patchset #1 (id:1) as
https://chromium.googlesource.com/chromium/src/+/f47de6fa1c432e87dc270ff96b10...