Revert of Delete the enable/disable layer squashing flags and settings.

Revert of Delete the enable/disable layer squashing flags and settings. (patchset #1 id:1 of https://codereview.chromium.org/785323002/)

Reason for revert:
The patch caused multiple blink layout tests to fail.

Test expectations dashboard: http://goo.gl/NvoO5S
Example failed build bot: http://build.chromium.org/p/chromium.webkit/builders/WebKit%20Linux/builds/41154

Original issue's description:
> Delete the enable/disable layer squashing flags and settings.
>
> TBR=jam,jochen
>
> Committed: https://crrev.com/f56bfaf1de4e66047ea9dda4cc7e31f074fb80df
> Cr-Commit-Position: refs/heads/master@{#307620}

TBR=chrishtr@chromium.org
NOTREECHECKS=true
NOTRY=true

Committed: https://crrev.com/dbef697979ade47295961b71c07e352a38fca611
Cr-Commit-Position: refs/heads/master@{#307714}

[lushnikov, 2014-12-10 16:34:22]

Created Revert of Delete the enable/disable layer squashing flags and settings.

[commit-bot: I haz the power, 2014-12-10 16:35:03]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/789163004/1

[lushnikov, 2014-12-10 16:35:19]

The CQ bit was unchecked by lushnikov@chromium.org

[commit-bot: I haz the power, 2014-12-10 16:35:25]

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

[lushnikov, 2014-12-10 16:35:40]

The CQ bit was checked by lushnikov@chromium.org

[commit-bot: I haz the power, 2014-12-10 16:36:49]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/789163004/1

[commit-bot: I haz the power, 2014-12-10 16:37:40]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2014-12-10 16:38:44]

Patchset 1 (id:??) landed as
https://crrev.com/dbef697979ade47295961b71c07e352a38fca611
Cr-Commit-Position: refs/heads/master@{#307714}