proposed freeze

[Benjamin Kosnik]

>Cooperation is greatly appreciated.

Thanks.

This freeze is now lifted.

However, an attempt is being made to keep 3.4.0 and 3.5.0 sources
in-sync until the 3.4.0 release. That way, we can branch off 3.5.0
sources when 3.4.0 is released, and tag this as libstdcxx_7.

Therefore, when checking in to mainline, either queue the same patch for
3.4.1, or ask explicitly for approval from Mark.

-benjamin