opengles Translator: DrawTex impl - don't draw if no textures enabled.

This fixes a crash caused by covgl (on Nvidia linux driver) when our implementation
of glDrawTexOES calls glDrawArrays with GL_TEXTURE_COORD_ARRAY enabled - but none of texture
units are enabled and no data passed by glTexCoordPointer

Change-Id: Id28b0c35a5a17b139ab196db0e434d2f0a490132
1 file changed