Support decltype as a simple-type-specifier.

This makes all sorts of fun examples work with decltype.
Reviewed by Richard Smith.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@148787 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Parse/ParseTentative.cpp b/lib/Parse/ParseTentative.cpp
index fe46456..4f80da2 100644
--- a/lib/Parse/ParseTentative.cpp
+++ b/lib/Parse/ParseTentative.cpp
@@ -1009,6 +1009,7 @@
   case tok::kw_float:
   case tok::kw_double:
   case tok::kw_void:
+  case tok::annot_decltype:
     if (NextToken().is(tok::l_paren))
       return TPResult::Ambiguous();
 
@@ -1038,10 +1039,6 @@
     return TPResult::True();
   }
 
-  // C++0x decltype support.
-  case tok::annot_decltype:
-    return TPResult::True();
-
   // C++0x type traits support
   case tok::kw___underlying_type:
     return TPResult::True();