Merged in SL-17967 (pull request #1113)

indra/llrender/llatmosphere.cpp

indra/llrender/llcubemap.cpp

indra/llrender/llcubemaparray.cpp

indra/llrender/llgl.cpp

indra/llrender/llglheaders.h

indra/llrender/llglslshader.cpp

indra/llrender/llglslshader.h

indra/llrender/llglstates.h

indra/llrender/llimagegl.cpp

indra/llrender/llpostprocess.cpp

indra/llrender/llpostprocess.h

indra/llrender/llrender.cpp

indra/llrender/llrendertarget.cpp

indra/llrender/llshadermgr.cpp

indra/llrender/llshadermgr.h

indra/llrender/llvertexbuffer.cpp

indra/llrender/llvertexbuffer.h

indra/llwindow/llopenglview-objc.mm

...ew/app_settings/shaders/class1/deferred/deferredUtil.glsl

...pp_settings/shaders/class2/deferred/reflectionProbeF.glsl