Fix #34714: cycles viewport render would restart when minimizing and unminimizing
a maximized Blender window in Ubuntu Unity. The window size would slightly change
as part of the unminimize effect.

Now cycles waits 0.2 seconds before restarting rendering after a viewport resize,
also a bit less flickery when changing the 3d view size in Blender itself.



git-svn-id: https://svn.blender.org/svnroot/bf-blender/trunk/blender@56278 954f8c5b-7b00-dc11-b283-0030488c597c