For all keywords already present, get correct when they could be identifiers, are reserved words, or are keywords, for all versions of ESSL and GLSL.

git-svn-id: https://cvs.khronos.org/svn/repos/ogl/trunk/ecosystem/public/sdk/tools/glslang@21282 e7fa87d3-cd2b-0410-9028-fcbf551c1848

Test/130.frag

@@ -9,6 +9,10 @@ precision highp float;
 in vec4 i;
 out vec4 o;
 
+in flat float fflat;
+in smooth float fsmooth;
+in noperspective float fnop;
+
 void main()
 {
 }