Fix an error in _save_OBE_DrawElements
Fix an error in _save_OBE_DrawElements

In the case that a buffer object is bound to
ELEMENT_ARRARY_BUFFER, it is invalid to directly
dereference indices passed to glDrawElements.

zz85/glsl-optimizer,dellis1972/glsl-optimizer,djreep81/glsl-optimizer,tokyovigilante/glsl-optimizer,KTXSoftware/glsl2agal,zeux/glsl-optimizer,tokyovigilante/glsl-optimizer,mcanthony/glsl-optimizer,bkaradzic/glsl-optimizer,metora/MesaGLSLCompiler,zeux/glsl-optimizer,zz85/glsl-optimizer,mapbox/glsl-optimizer,mapbox/glsl-optimizer,mapbox/glsl-optimizer,zz85/glsl-optimizer,dellis1972/glsl-optimizer,benaadams/glsl-optimizer,dellis1972/glsl-optimizer,adobe/glsl2agal,wolf96/glsl-optimizer,djreep81/glsl-optimizer,tokyovigilante/glsl-optimizer,zeux/glsl-optimizer,jbarczak/glsl-optimizer,dellis1972/glsl-optimizer,bkaradzic/glsl-optimizer,djreep81/glsl-optimizer,KTXSoftware/glsl2agal,wolf96/glsl-optimizer,bkaradzic/glsl-optimizer,zeux/glsl-optimizer,mcanthony/glsl-optimizer,jbarczak/glsl-optimizer,metora/MesaGLSLCompiler,zz85/glsl-optimizer,wolf96/glsl-optimizer,KTXSoftware/glsl2agal,djreep81/glsl-optimizer,mapbox/glsl-optimizer,mcanthony/glsl-optimizer,jbarczak/glsl-optimizer,benaadams/glsl-optimizer,dellis1972/glsl-optimizer,adobe/glsl2agal,tokyovigilante/glsl-optimizer,KTXSoftware/glsl2agal,wolf96/glsl-optimizer,mcanthony/glsl-optimizer,bkaradzic/glsl-optimizer,tokyovigilante/glsl-optimizer,benaadams/glsl-optimizer,mapbox/glsl-optimizer,djreep81/glsl-optimizer,zeux/glsl-optimizer,adobe/glsl2agal,KTXSoftware/glsl2agal,mcanthony/glsl-optimizer,jbarczak/glsl-optimizer,wolf96/glsl-optimizer,adobe/glsl2agal,metora/MesaGLSLCompiler,zz85/glsl-optimizer,bkaradzic/glsl-optimizer,benaadams/glsl-optimizer,jbarczak/glsl-optimizer,benaadams/glsl-optimizer,benaadams/glsl-optimizer,zz85/glsl-optimizer,adobe/glsl2agal