Fix High Contrast extension

Fix High Contrast extension

Chrome 45+ doesn't let you set a filter on the HTML element anymore,
so we have to create a separate element with low z-index and copy the
background.

In addition, the filter seems to need to be fixed-positioned or Chrome
won't properly update it.

BUG=534971, 591476
NOTRY=true

Review-Url: https://codereview.chromium.org/2769743005
Cr-Commit-Position: refs/heads/master@{#460158}
Committed: https://chromium.googlesource.com/chromium/src/+/adaaccd59252c8fb9af08fcf65e8b78f25f053b2

[dmazzoni, 2017-03-24 21:27:03]

dmazzoni@chromium.org changed reviewers:
+ wnwen@chromium.org

[dmazzoni, 2017-03-24 21:27:03]

The previous patchset was incomplete.

This change has all of the hacks ("fixes") to the
high contrast extension.

Maybe you could help me review this and then we can
try to apply the same to the color enhancer?

I think the key difference is the fixed positioning.

[Peter Wen, 2017-03-27 18:03:35]

lgtm, filter fixes work for colorenhancer

[dmazzoni, 2017-03-28 17:30:37]

Description was changed from

==========
Fix High Contrast extension

Chrome 45+ doesn't let you set a filter on the HTML element anymore,
so we have to create a separate element with low z-index and copy the
background.

In addition, the filter seems to need to be fixed-positioned or Chrome
won't properly update it.

BUG=534971, 591476
==========

to

==========
Fix High Contrast extension

Chrome 45+ doesn't let you set a filter on the HTML element anymore,
so we have to create a separate element with low z-index and copy the
background.

In addition, the filter seems to need to be fixed-positioned or Chrome
won't properly update it.

BUG=534971, 591476
NOTRY=true
==========

[dmazzoni, 2017-03-28 17:30:42]

The CQ bit was checked by dmazzoni@chromium.org

[commit-bot: I haz the power, 2017-03-28 17:31:14]

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, 2017-03-28 17:36:49]

CQ is committing da patch.

Bot data: {"patchset_id": 1, "attempt_start_ts": 1490722242564510, "parent_rev":
"010bed54423a428a1812dfe7eab7ed95c5bf9982", "commit_rev":
"adaaccd59252c8fb9af08fcf65e8b78f25f053b2"}

[commit-bot: I haz the power, 2017-03-28 17:37:37]

Description was changed from

==========
Fix High Contrast extension

Chrome 45+ doesn't let you set a filter on the HTML element anymore,
so we have to create a separate element with low z-index and copy the
background.

In addition, the filter seems to need to be fixed-positioned or Chrome
won't properly update it.

BUG=534971, 591476
NOTRY=true
==========

to

==========
Fix High Contrast extension

Chrome 45+ doesn't let you set a filter on the HTML element anymore,
so we have to create a separate element with low z-index and copy the
background.

In addition, the filter seems to need to be fixed-positioned or Chrome
won't properly update it.

BUG=534971, 591476
NOTRY=true

Review-Url: https://codereview.chromium.org/2769743005
Cr-Commit-Position: refs/heads/master@{#460158}
Committed:
https://chromium.googlesource.com/chromium/src/+/adaaccd59252c8fb9af08fcf65e8...
==========

[commit-bot: I haz the power, 2017-03-28 17:37:38]

Committed patchset #1 (id:1) as
https://chromium.googlesource.com/chromium/src/+/adaaccd59252c8fb9af08fcf65e8...