Add OpenCL samplers as Clang builtin types and check sampler related restrictions.

llvm-svn: 174601
diff --git a/clang/lib/Sema/SemaTemplateVariadic.cpp b/clang/lib/Sema/SemaTemplateVariadic.cpp
index 470896e..c13a2f6 100644
--- a/clang/lib/Sema/SemaTemplateVariadic.cpp
+++ b/clang/lib/Sema/SemaTemplateVariadic.cpp
@@ -737,6 +737,7 @@
   case TST_image2d_t:
   case TST_image2d_array_t:
   case TST_image3d_t:
+  case TST_sampler_t:
   case TST_event_t:
   case TST_error:
     break;