Revert of [Chromoting] Disable building 64bit chromoting.msi file. (patchset #2 id:60001 of )

Reason for revert:
Breaks the build:

Original issue's description:
> [Chromoting] Disable building 64bit chromoting.msi file.
> A recent bug has been reported by AJ, which is due to a
> bad signing parameter we are using. It causes the 64 bit signed MSI file won't
> be able to execute correctly in curtain mode.
> Since we do not release 64bit msi, we should not spend time to build it.
> BUG=
> Committed:
> Cr-Commit-Position: refs/heads/master@{#401031},
# Not skipping CQ checks because original CL landed more than 1 days ago.

Cr-Commit-Position: refs/heads/master@{#401487}
2 files changed