Revert of Fixes for contenteditable caret and selection handling in Windows.

Revert of Fixes for contenteditable caret and selection handling in Windows. (patchset #14 id:260001 of https://codereview.chromium.org/1377733002/ )

Reason for revert:
Breaks reporting of the selection when the focus is on a text leaf that is not an immediate sibling of the nearest non-text ancestor of the current object.

Original issue's description:
> Fixes for contenteditable caret and selection handling in Windows.
> 
> 1. Reports a valid selection endpoint even when either the start or end of the selection fall outside the object.
> <div contenteditable>this <selection_start>is a <a href="#">link<selection_end></a>.</div>
> selection_start on the link element would be given as 0.
> 2. Does not report any selection on a parent object if there is no selection on the child objects.
> <div contenteditable><p>hi</p></div>
> nSelections on the div should be 0.
> BUG=527440
> R=dmazzoni@chromium.org
> 
> Committed: https://crrev.com/d816a9211de3c355f0de5051fa5c517ef2321e1a
> Cr-Commit-Position: refs/heads/master@{#352236}

TBR=dmazzoni@chromium.org
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=527440

[nektarios, 2015-10-03 04:46:24]

Created Revert of Fixes for contenteditable caret and selection handling in
Windows.

[commit-bot: I haz the power, 2015-10-03 04:46:49]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1388593002/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1388593002/1

[commit-bot: I haz the power, 2015-10-03 04:46:50]

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

[commit-bot: I haz the power, 2015-10-03 04:46:51]

No L-G-T-M from a valid reviewer yet. Only full committers are accepted.
Even if an L-G-T-M may have been provided, it was from a non-committer,
_not_ a full super star committer.
See http://www.chromium.org/getting-involved/become-a-committer
Note that this has nothing to do with OWNERS files.

[Daniele Castagna, 2015-10-05 19:05:17]

dcastagna@chromium.org changed reviewers:
+ dcastagna@chromium.org

[Daniele Castagna, 2015-10-05 19:05:17]

Closing it since Nektar is working on a follow-up patch.