Implement default layout qualifiers at global and block levels with proper inheritance. Also add more error checking of qualifiers.

git-svn-id: https://cvs.khronos.org/svn/repos/ogl/trunk/ecosystem/public/sdk/tools/glslang@21107 e7fa87d3-cd2b-0410-9028-fcbf551c1848

Test/300layout.vert

@@ -12,6 +12,8 @@ layout(std140) uniform Transform { // layout of this block is std140
     mat4 M1; // row_major
     layout(column_major) mat4 M2; // column major
     mat3 N1; // row_major
+    centroid float badf;  // ERROR
+    in float badg;        // ERROR
 } tblock;
 
 uniform T2 { // layout of this block is shared
@@ -26,6 +28,10 @@ layout(column_major) uniform T3 { // shared and column_major
     int b;  // ERROR, redefinition (needs to be last member of block for testing, following members are skipped)
 };
 
+out badout {  // ERROR
+    float f;
+};
+
 void main()
 {
     pos = p * (tblock.M1 + tblock.M2 + M4 + M3 + t2m);