This change enables applications to create a private virtual
display that renders its content to a surface of its own creation.
The display is private in the sense that only the application
that owns the display is allowed to place windows upon it.
Mirroring and blanking is also disabled for these displays.
Bug: 9192512
Change-Id: I852ea07f0c7df1d244e354e3daca3a6960285ca0
a506a6ec94