LayoutTheme: Invalidate cache on WebThemeEngine change.

LayoutTheme: Invalidate cache on WebThemeEngine change.

A LayoutThemeDefault instance can be associated to a real
WebThemeEngine or a mock WebThemeEngine, which have different
metrics. We need to invalidate a cached value when a WebThemeEngine is
switched.

The bug affects only layout tests.

BUG=673754
Review-Url: https://codereview.chromium.org/2627773002
Cr-Commit-Position: refs/heads/master@{#442799}
Committed: https://chromium.googlesource.com/chromium/src/+/b554c05ac115a02e49b478fb737604719b479efb

[tkent, 2017-01-11 01:04:36]

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

[commit-bot: I haz the power, 2017-01-11 01:05:18]

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

[tkent, 2017-01-11 02:17:59]

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

[tkent, 2017-01-11 02:17:59]

keishi@, would you review this please?

[keishi, 2017-01-11 02:19:27]

LGTM

[commit-bot: I haz the power, 2017-01-11 04:20:39]

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

[commit-bot: I haz the power, 2017-01-11 04:20:40]

Dry run: This issue passed the CQ dry run.

[tkent, 2017-01-11 04:21:24]

The CQ bit was checked by tkent@chromium.org

[commit-bot: I haz the power, 2017-01-11 04:21:46]

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, 2017-01-11 04:25:35]

CQ is committing da patch.

Bot data: {"patchset_id": 1, "attempt_start_ts": 1484108484310770, "parent_rev":
"275b25d4d93d0eeb6277b3f4f24fbce319ffe1fe", "commit_rev":
"b554c05ac115a02e49b478fb737604719b479efb"}

[commit-bot: I haz the power, 2017-01-11 04:26:01]

Description was changed from

==========
LayoutTheme: Invalidate cache on WebThemeEngine change.

A LayoutThemeDefault instance can be associated to a real
WebThemeEngine or a mock WebThemeEngine, which have different
metrics. We need to invalidate a cached value when a WebThemeEngine is
switched.

The bug affects only layout tests.

BUG=673754
==========

to

==========
LayoutTheme: Invalidate cache on WebThemeEngine change.

A LayoutThemeDefault instance can be associated to a real
WebThemeEngine or a mock WebThemeEngine, which have different
metrics. We need to invalidate a cached value when a WebThemeEngine is
switched.

The bug affects only layout tests.

BUG=673754

Review-Url: https://codereview.chromium.org/2627773002
Cr-Commit-Position: refs/heads/master@{#442799}
Committed:
https://chromium.googlesource.com/chromium/src/+/b554c05ac115a02e49b478fb7376...
==========

[commit-bot: I haz the power, 2017-01-11 04:26:02]

Committed patchset #1 (id:1) as
https://chromium.googlesource.com/chromium/src/+/b554c05ac115a02e49b478fb7376...