Revert of Use Clang's update.py --print-revision everywhere.

Revert of Use Clang's update.py --print-revision everywhere. (patchset #4 id:60001 of https://codereview.chromium.org/1127233002/)

Reason for revert:
Looks like this broke the world: http://build.chromium.org/p/chromium.fyi/console?category=win%20clang

Original issue's description:
> Use Clang's update.py --print-revision everywhere.
>
> Since yesterday, it works on Windows. This allows us to not
> completely clobber the build from update.py each time, since the
> build system tracks the dependency instead.
>
> It should also be possible to use this from gn, so we can delete the
> posix-print-revision.py script. The only problem was that the
> hack we use for fixing the output in gclient runhooks didn't work.
> I've adjusted that to not fail when the hack doesn't work.
>
> BUG=483065
>
> Committed: https://crrev.com/828bba82c5ed315cf073ad9599c0d5334a9a403d
> Cr-Commit-Position: refs/heads/master@{#328634}

TBR=scottmg@chromium.org,hans@chromium.org
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=483065
Committed: https://crrev.com/05320c6a7b8695c843c6d4de10261e7a65fafcb3
Cr-Commit-Position: refs/heads/master@{#328672}

[Nico, 2015-05-07 01:14:25]

Created Revert of Use Clang's update.py --print-revision everywhere.

[commit-bot: I haz the power, 2015-05-07 01:15:47]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1131813002/1

[hans, 2015-05-07 01:18:20]

Thanks for watching the tree.

[commit-bot: I haz the power, 2015-05-07 01:20:10]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2015-05-07 01:21:02]

Patchset 1 (id:??) landed as
https://crrev.com/05320c6a7b8695c843c6d4de10261e7a65fafcb3
Cr-Commit-Position: refs/heads/master@{#328672}