Revert of Convert enable_pre_sync_backup flag to new flags system.

Revert of Convert enable_pre_sync_backup flag to new flags system. (patchset #4 id:60001 of https://codereview.chromium.org/1478623004/ )

Reason for revert:
Busted iOS http://build.chromium.org/p/chromium.mac/builders/iOS_Device/builds/30182/steps/compile/logs/stdio

Original issue's description:
> Convert enable_pre_sync_backup flag to new flags system.
>
> This flag's usage is very isolated so is a good candidate for the new system. There is now a generated header for the #define rather than a global define.
>
> Committed: https://crrev.com/bc4bccdacc16ccdf314870049033e03c463e478e
> Cr-Commit-Position: refs/heads/master@{#362284}

TBR=zea@chromium.org
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true

Committed: https://crrev.com/b23c180344c5df1f3fbdc8c8387d30e9c9ef8a2f
Cr-Commit-Position: refs/heads/master@{#362297}

[brettw, 2015-12-01 00:35:04]

Created Revert of Convert enable_pre_sync_backup flag to new flags system.

[commit-bot: I haz the power, 2015-12-01 00:42:14]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1485933002/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1485933002/1

[commit-bot: I haz the power, 2015-12-01 00:48:31]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2015-12-01 00:49:29]

Description was changed from

==========
Revert of Convert enable_pre_sync_backup flag to new flags system. (patchset #4
id:60001 of https://codereview.chromium.org/1478623004/ )

Reason for revert:
Busted iOS
http://build.chromium.org/p/chromium.mac/builders/iOS_Device/builds/30182/ste...

Original issue's description:
> Convert enable_pre_sync_backup flag to new flags system.
> 
> This flag's usage is very isolated so is a good candidate for the new system.
There is now a generated header for the #define rather than a global define.
> 
> Committed: https://crrev.com/bc4bccdacc16ccdf314870049033e03c463e478e
> Cr-Commit-Position: refs/heads/master@{#362284}

TBR=zea@chromium.org
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
==========

to

==========
Revert of Convert enable_pre_sync_backup flag to new flags system. (patchset #4
id:60001 of https://codereview.chromium.org/1478623004/ )

Reason for revert:
Busted iOS
http://build.chromium.org/p/chromium.mac/builders/iOS_Device/builds/30182/ste...

Original issue's description:
> Convert enable_pre_sync_backup flag to new flags system.
>
> This flag's usage is very isolated so is a good candidate for the new system.
There is now a generated header for the #define rather than a global define.
>
> Committed: https://crrev.com/bc4bccdacc16ccdf314870049033e03c463e478e
> Cr-Commit-Position: refs/heads/master@{#362284}

TBR=zea@chromium.org
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true

Committed: https://crrev.com/b23c180344c5df1f3fbdc8c8387d30e9c9ef8a2f
Cr-Commit-Position: refs/heads/master@{#362297}
==========

[commit-bot: I haz the power, 2015-12-01 00:49:29]

Patchset 1 (id:??) landed as
https://crrev.com/b23c180344c5df1f3fbdc8c8387d30e9c9ef8a2f
Cr-Commit-Position: refs/heads/master@{#362297}