Remove unnecessary and inappropriate forward-declaration of Sema from
AST.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@374952 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/include/clang/AST/ExprCXX.h b/include/clang/AST/ExprCXX.h
index 57ccba8..9c05de6 100644
--- a/include/clang/AST/ExprCXX.h
+++ b/include/clang/AST/ExprCXX.h
@@ -57,7 +57,6 @@
 class LambdaCapture;
 class NonTypeTemplateParmDecl;
 class TemplateParameterList;
-class Sema;
 
 //===--------------------------------------------------------------------===//
 // C++ Expressions.