Make layout tests in editing/deleting and editing/execCommand to use w3c test harness

Make layout tests in editing/deleting and editing/execCommand to use w3c test harness

This patch makes following tests to use w3c test harness to simplify tests
and avoid to compare pixel results.

Pixel results aren't essential for tests changed in this patch and when
we enable asynchronous spell checking, pixel result contains red wave lines for
miss spelled. These read wave lines aren't related what we want to test.

This patch is a preparation of getting rid of synchronous code path for
spellcheck to enable asynchronous spell checking always.

BUG=295722
TEST=n/a; no behavior changes

Committed: https://crrev.com/d076ca806251e4b636b421eb46ca04d14366b2cc
Cr-Commit-Position: refs/heads/master@{#360538}

[yosin_UTC9, 2015-11-19 05:55:14]

Description was changed from

==========
2015-11-19T13:54:41

BUG=295772
==========

to

==========
Make layout tests in editing/deleting and editing/execCommand to use w3c test
harness

This patch makes following tests to use w3c test harness to simplify tests
and avoid to compare pixel results.

Pixel results aren't essential for tests changed in this patch and when
we enable asynchronous spell checking, pixel result contains red wave lines for
miss spelled. These read wave lines aren't related what we want to test.

This patch is a preparation of getting rid of synchronous code path for
spellcheck to enable asynchronous spell checking always.

BUG=295722
TEST=n/a; no behavior changes
==========

[yosin_UTC9, 2015-11-19 05:57:45]

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

[yosin_UTC9, 2015-11-19 05:57:45]

PTAL

[yosin_UTC9, 2015-11-19 06:22:57]

PTAL

[hajimehoshi, 2015-11-19 06:25:52]

lgtm

[yosin_UTC9, 2015-11-19 06:46:16]

The CQ bit was checked by yosin@chromium.org

[commit-bot: I haz the power, 2015-11-19 06:46:50]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1459783003/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1459783003/1

[commit-bot: I haz the power, 2015-11-19 06:52:25]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2015-11-19 06:53:27]

Patchset 1 (id:??) landed as
https://crrev.com/d076ca806251e4b636b421eb46ca04d14366b2cc
Cr-Commit-Position: refs/heads/master@{#360538}