Introduce firstEditablePositionAfterPositionInRoot()

Introduce firstEditablePositionAfterPositionInRoot()

This patch introduces |firstEditablePositionAfterPositionInRoot()| as pair of
|lastEditablePositionBeforePositionInRoot()| to make debugging easier for
improving code health.

This patch is a preparation of making selection to handle granularity for web
component, http://crrev.com/1277863002

BUG=513568
TEST=n/a; No behavior changes

Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=201220

[yosin_UTC9, 2015-08-26 08:24:44]

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

[yosin_UTC9, 2015-08-26 08:24:54]

PTAL

[hajimehoshi, 2015-08-26 08:46:35]

lgtm

[yosin_UTC9, 2015-08-26 08:48:01]

The CQ bit was checked by yosin@chromium.org

[commit-bot: I haz the power, 2015-08-26 08:48:07]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1316063002/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1316063002/1

[yoichio, 2015-08-26 08:58:26]

https://codereview.chromium.org/1316063002/diff/1/Source/core/editing/Editing...
File Source/core/editing/EditingUtilitiesTest.cpp (right):

https://codereview.chromium.org/1316063002/diff/1/Source/core/editing/Editing...
Source/core/editing/EditingUtilitiesTest.cpp:26: EXPECT_EQ(Position(one, 0),
firstEditablePositionAfterPositionInRoot(Position(one, 0), host));
Looks getting same position though function name includes 'After'.
How about naming 'SameOrAfter' or something?

[yosin_UTC9, 2015-08-26 09:17:19]

On 2015/08/26 08:58:26, yoichio wrote:
>
https://codereview.chromium.org/1316063002/diff/1/Source/core/editing/Editing...
> File Source/core/editing/EditingUtilitiesTest.cpp (right):
> 
>
https://codereview.chromium.org/1316063002/diff/1/Source/core/editing/Editing...
> Source/core/editing/EditingUtilitiesTest.cpp:26: EXPECT_EQ(Position(one, 0),
> firstEditablePositionAfterPositionInRoot(Position(one, 0), host));
> Looks getting same position though function name includes 'After'.
> How about naming 'SameOrAfter' or something?

There is honorEditingBoundaryAtOrAfter(), 
so firstEditablePositionAtOrAfterPositionInRoot(),
and lastEditablePositionAtOrAfterPositionInRoot()?
or
editablePositionInRootAtOrAfterPosition()
editablePositionInRootAtOrBeforePosition()

Once we have agreement, I'll create a patch for renaming both.

[commit-bot: I haz the power, 2015-08-26 09:31:08]

Committed patchset #1 (id:1) as
https://src.chromium.org/viewvc/blink?view=rev&revision=201220