surfacemediasource: Do not assume that onBuffersReleased means EOS

When using a surface media source the callee may release/allocate
buffers, for instance when negotiating formats with an external source.

This means that onBuffersReleased might be called but that does not mean
that there isn't a producer in the other end, just that it might have changed
formats.

This patch solves that by if-deffing a CAF addition that makes wifi-display
non-functional in some devices.

Change-Id: Ie702c1b4b32f0b00388beea9cf2ff032a50b0bdb