Refactor DocumentMarkerController to use SynchronousMutationObserver

Refactor DocumentMarkerController to use SynchronousMutationObserver

I had a previous CL up where I made this change combined with some behavioral
changes to DocumentMarkerController::shiftMarker():
https://codereview.chromium.org/2692093003

In this CL, I am only refactoring DMC to use SMO without making any other
behavioral changes. Whereas the other CL did all the marker updates in one pass
through shiftMarkers(), the most straightforward way to avoid introducing any
behavioral changes is to call removeMarkers() on the text being replaced, shift
the markers for the remove, and then shift the markers in the other direction
for the insert.

I will update the marker-shifting behavior to handle text replacement more
gracefully (i.e. not splitting the markers when text is removed, keeping
replaced text at the start/end of the marked range inside the range after
replacement) in a follow-up CL.

BUG=682878
Review-Url: https://codereview.chromium.org/2755953004
Cr-Commit-Position: refs/heads/master@{#458518}
Committed: https://chromium.googlesource.com/chromium/src/+/c8529921548accf5f93751f6f997bebe7e0683bd

[rlanday, 2017-03-17 17:49:59]

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

[commit-bot: I haz the power, 2017-03-17 17:50:29]

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

[rlanday, 2017-03-17 17:59:06]

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

[rlanday, 2017-03-17 17:59:06]

rlanday@chromium.org changed required reviewers:
+ yosin@chromium.org

[commit-bot: I haz the power, 2017-03-17 19:16:26]

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

[commit-bot: I haz the power, 2017-03-17 19:16:27]

Dry run: This issue passed the CQ dry run.

[yosin_UTC9, 2017-03-21 03:33:45]

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

[yosin_UTC9, 2017-03-21 03:33:45]

lgtm

I really love using SMO!

+tkent@ for core/dom changes.

[tkent, 2017-03-21 03:37:00]

lgtm

[rlanday, 2017-03-21 18:07:56]

The CQ bit was checked by rlanday@chromium.org

[commit-bot: I haz the power, 2017-03-21 18:08:34]

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, 2017-03-21 19:46:13]

CQ is committing da patch.

Bot data: {"patchset_id": 1, "attempt_start_ts": 1490119676810250, "parent_rev":
"5ffc5e0008e9e381f23896ecc010da32f06a0dd5", "commit_rev":
"c8529921548accf5f93751f6f997bebe7e0683bd"}

[commit-bot: I haz the power, 2017-03-21 19:46:59]

Description was changed from

==========
Refactor DocumentMarkerController to use SynchronousMutationObserver

I had a previous CL up where I made this change combined with some behavioral
changes to DocumentMarkerController::shiftMarker():
https://codereview.chromium.org/2692093003

In this CL, I am only refactoring DMC to use SMO without making any other
behavioral changes. Whereas the other CL did all the marker updates in one pass
through shiftMarkers(), the most straightforward way to avoid introducing any
behavioral changes is to call removeMarkers() on the text being replaced, shift
the markers for the remove, and then shift the markers in the other direction
for the insert.

I will update the marker-shifting behavior to handle text replacement more
gracefully (i.e. not splitting the markers when text is removed, keeping
replaced text at the start/end of the marked range inside the range after
replacement) in a follow-up CL.

BUG=682878
==========

to

==========
Refactor DocumentMarkerController to use SynchronousMutationObserver

I had a previous CL up where I made this change combined with some behavioral
changes to DocumentMarkerController::shiftMarker():
https://codereview.chromium.org/2692093003

In this CL, I am only refactoring DMC to use SMO without making any other
behavioral changes. Whereas the other CL did all the marker updates in one pass
through shiftMarkers(), the most straightforward way to avoid introducing any
behavioral changes is to call removeMarkers() on the text being replaced, shift
the markers for the remove, and then shift the markers in the other direction
for the insert.

I will update the marker-shifting behavior to handle text replacement more
gracefully (i.e. not splitting the markers when text is removed, keeping
replaced text at the start/end of the marked range inside the range after
replacement) in a follow-up CL.

BUG=682878

Review-Url: https://codereview.chromium.org/2755953004
Cr-Commit-Position: refs/heads/master@{#458518}
Committed:
https://chromium.googlesource.com/chromium/src/+/c8529921548accf5f93751f6f997...
==========

[commit-bot: I haz the power, 2017-03-21 19:47:01]

Committed patchset #1 (id:1) as
https://chromium.googlesource.com/chromium/src/+/c8529921548accf5f93751f6f997...