shaders branch: YUV conversion code path selection based on GL version.
shaders branch: YUV conversion code path selection based on GL version.

svn path=/branches/libavg_shaders/; revision=7285

hoodie/libavg,th3infinity/libavg,scotty007/libavg,libavg/libavg,yyd01245/libavg,scotty007/libavg,libavg/libavg,libavg/libavg,yyd01245/libavg,libavg/libavg,scotty007/libavg,th3infinity/libavg,yyd01245/libavg,yyd01245/libavg,scotty007/libavg,hoodie/libavg,th3infinity/libavg,hoodie/libavg,th3infinity/libavg,hoodie/libavg