[AST] Remove unused Sema includes to fix a cyclic dependency from Sema to AST

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@374893 91177308-0d34-0410-b5e6-96231b3b80d8

lib/AST/ExprCXX.cpp

@@ -28,9 +28,6 @@
 #include "clang/Basic/OperatorKinds.h"
 #include "clang/Basic/SourceLocation.h"
 #include "clang/Basic/Specifiers.h"
-#include "clang/Sema/Template.h"
-#include "clang/Sema/SemaDiagnostic.h"
-#include "clang/Sema/Sema.h"
 #include "llvm/ADT/ArrayRef.h"
 #include "llvm/Support/Casting.h"
 #include "llvm/Support/ErrorHandling.h"
@@ -1761,4 +1758,4 @@ ConceptSpecializationExpr::Create(ASTContext &C, EmptyShell Empty,
   void *Buffer = C.Allocate(totalSizeToAlloc<TemplateArgument>(
                                 NumTemplateArgs));
   return new (Buffer) ConceptSpecializationExpr(Empty, NumTemplateArgs);
-}
+}