Do qualifier-based checking independent of declaring a variable. Bug 11903.

git-svn-id: https://cvs.khronos.org/svn/repos/ogl/trunk/ecosystem/public/sdk/tools/glslang@28502 e7fa87d3-cd2b-0410-9028-fcbf551c1848

Test/100.frag

@@ -46,7 +46,7 @@ float fa[];              // ERROR
 float f13;
 invariant f13;           // ERROR
 struct S { int a; };
-invariant S;
+invariant S;             // ERROR, not an input or output
 invariant float fi;      // ERROR
 varying vec4 av;
 invariant av;            // okay in v100
@@ -194,4 +194,6 @@ void badswizzle()
     a.method(); // ERROR
 }
 
+#pragma STDGL invariant(all)
+
 uniform samplerExternalOES badExt;  // syntax ERROR