emulator opengl : unit-test renderer  GLESv2

Make the unit test renderer (ut_renderer) encode GLESv2 commands.
A rendering thread has both V1 & V2 decoder object, and tryies to decode
commands of the two protocols from the stream.
Context creating is taking into account the API version and creates context
accordingly.
Decoder data is shared between the V1 & V2 decoders and applied to both of
them on makeCurrent (regardless to the requested context version)

Change-Id: If78e84310e5dcd22108c19656051b138b22e3c9f
4 files changed