Comment 8 for bug 1309942

Sorry, this feature is not supported anymore for consistency reason: the ubuntu desktop moved the window controls to the left years ago, and unity designers decided to move window controls to the left of the windows when they are maximized.
So, having window controls on the right for restored windows, and to the left when they're maximized just didn't make any sense.

So, when implementing the new decorations in unity, we just decided to not support this anymore, reducing a lot the complexity of the code involved in layouting and disposing the elements in the decorations.

Some of the reasons have been explained in this post also: http://blog.3v1n0.net/informatica/linux/ubuntu-introducing-locally-integrated-menus-to-unity-7/