WindowlessWindowManager: Set size when creating surface

When we set the buffer size from relayout window, there is a race
condition where the client may then submit its first buffer but the
transaction hasnt applied yet on the SF side and so the buffer is
rejected. Setting a defualt size when creating fixes this. Luckily
SurfaceControlViewHost size is known at add time, since we force the
window size based on the values passed in to the SurfaceControlViewHost API.

Bug: 157153874
Test: Existing tests pass
Change-Id: I2566844aea81df92f1694f43254a480fc3b3c019