am 1ecf5d28: Re-implementation of large screen support using window manager.  * added background filler surface to fill the outer rim. Using the same layer as dim surface because    they never co-exists (in the same window)  * clean up the obsolete code in Compatibilt

Merge commit '1ecf5d28817f0a051e77488380dcd5bc622ea169'

* commit '1ecf5d28817f0a051e77488380dcd5bc622ea169':
  Re-implementation of large screen support using window manager.