Lazy shader update. attribute -> ATTRIBUTE, varying -> VARYING. Moved some shader preprocessor stuff from llviewershadermgr.cpp to llshadermgr.cpp to match LL (although it looks more messy)

indra/newview/app_settings/shaders/class3/deferred/giDownsampleF.glsl

@@ -17,7 +17,7 @@ uniform int kern_length;
 uniform float kern_scale;
 uniform vec3 blur_quad;
 
-varying vec2 vary_fragcoord;
+VARYING vec2 vary_fragcoord;
 
 uniform mat4 inv_proj;
 uniform vec2 screen_res;