Make SelectionEditor::markCacheDirty() not to reset cached value if it has been cleared

Make SelectionEditor::markCacheDirty() not to reset cached value if it has been cleared

This patch makes |SelectionEditor::markCacheDirty()| not to reset cached
|VisibleSeleciton| and |VisibleSelectionInFlatTree| when we've already cleard,
calling default constructor of |VisibleSelection| and
|VisibleSelectionInFlatTree| and copying them, to make |markCacheDirty()|
faster.

In "PerformanceTests/Bindings/append-child.html", |markCacheDirty()| takes
5.26% of |ContainerNode::appendChild()|.

In "PerformanceTests/DOM/inner_html_with_selection.html", |markCacheDirty()|
takes 8.56% of |ContainerNode::appendChild()|.


BUG=692939, 693458
TEST=n/a; no behavior changes

Review-Url: https://codereview.chromium.org/2708533002
Cr-Commit-Position: refs/heads/master@{#451567}
Committed: https://chromium.googlesource.com/chromium/src/+/54210329887cfd683e71722b93a5e05b95f5e12d

[yosin_UTC9, 2017-02-20 03:40:32]

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

[commit-bot: I haz the power, 2017-02-20 03:40:46]

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

[yosin_UTC9, 2017-02-20 04:04:25]

Description was changed from

==========
2017-02-20T12:38:08

2017-02-20T12:38:04

BUG=
==========

to

==========
Make SelectionEditor::markCacheDirty() not to reset cached value if it has been
cleared

This patch makes |SelectionEditor::markCacheDirty()| not to reset cached
|VisibleSeleciton| and |VisibleSelectionInFlatTree| when we've already cleard,
calling default constructor of |VisibleSelection| and
|VisibleSelectionInFlatTree| and copying them, to make |markCacheDirty()|
faster.

In "PerformanceTests/Bindings/append-child.html", |markCacheDirty()| takes
5.26% of |ContainerNode::appendChild()|.

In "PerformanceTests/DOM/inner_html_with_selection.html", |markCacheDirty()|
takes 8.56% of |ContainerNode::appendChild()|.


BUG=692939,693458
TEST=n/a; no behavior changes
==========

[yosin_UTC9, 2017-02-20 04:04:39]

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

[yosin_UTC9, 2017-02-20 04:04:40]

PTAL

[tkent, 2017-02-20 04:07:36]

lgtm

[yosin_UTC9, 2017-02-20 04:21:22]

The CQ bit was unchecked by yosin@chromium.org

[yosin_UTC9, 2017-02-20 04:21:26]

The CQ bit was checked by yosin@chromium.org

[commit-bot: I haz the power, 2017-02-20 04:21:32]

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, 2017-02-20 05:53:48]

CQ is committing da patch.

Bot data: {"patchset_id": 1, "attempt_start_ts": 1487564486797170, "parent_rev":
"b21d309ca9519eaa367e39a2ee8e447e955718ac", "commit_rev":
"54210329887cfd683e71722b93a5e05b95f5e12d"}

[commit-bot: I haz the power, 2017-02-20 05:54:22]

Description was changed from

==========
Make SelectionEditor::markCacheDirty() not to reset cached value if it has been
cleared

This patch makes |SelectionEditor::markCacheDirty()| not to reset cached
|VisibleSeleciton| and |VisibleSelectionInFlatTree| when we've already cleard,
calling default constructor of |VisibleSelection| and
|VisibleSelectionInFlatTree| and copying them, to make |markCacheDirty()|
faster.

In "PerformanceTests/Bindings/append-child.html", |markCacheDirty()| takes
5.26% of |ContainerNode::appendChild()|.

In "PerformanceTests/DOM/inner_html_with_selection.html", |markCacheDirty()|
takes 8.56% of |ContainerNode::appendChild()|.


BUG=692939,693458
TEST=n/a; no behavior changes
==========

to

==========
Make SelectionEditor::markCacheDirty() not to reset cached value if it has been
cleared

This patch makes |SelectionEditor::markCacheDirty()| not to reset cached
|VisibleSeleciton| and |VisibleSelectionInFlatTree| when we've already cleard,
calling default constructor of |VisibleSelection| and
|VisibleSelectionInFlatTree| and copying them, to make |markCacheDirty()|
faster.

In "PerformanceTests/Bindings/append-child.html", |markCacheDirty()| takes
5.26% of |ContainerNode::appendChild()|.

In "PerformanceTests/DOM/inner_html_with_selection.html", |markCacheDirty()|
takes 8.56% of |ContainerNode::appendChild()|.


BUG=692939,693458
TEST=n/a; no behavior changes

Review-Url: https://codereview.chromium.org/2708533002
Cr-Commit-Position: refs/heads/master@{#451567}
Committed:
https://chromium.googlesource.com/chromium/src/+/54210329887cfd683e71722b93a5...
==========

[commit-bot: I haz the power, 2017-02-20 05:54:23]

Committed patchset #1 (id:1) as
https://chromium.googlesource.com/chromium/src/+/54210329887cfd683e71722b93a5...