ISurface was only used to get the IGraphicBufferProducer from
a Layer. It's now replaced by a BBinder subclass / IBinder and
is only used as a handle to the surface, to both refer to it
and manage its life-time.
Also cleaned-up a bit the ISurfaceComposer interface and
"create layer" code path.
Change-Id: I68d0e02d57b862cffb31d5168c3bc10cea0906eb
Temporary, to fix weekend build, until we get Nvidia code drop.
This reverts commit 9a867a8798
DO NOT MERGE
Change-Id: I7b5dbc4db46ef3d97dc8598057d5487d6971178b
