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
0c01f32aa2