Some utilities for using the smart pointers in Actions, especially Sema. Convert a few functions.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@60983 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Parse/ParseStmt.cpp b/lib/Parse/ParseStmt.cpp
index ed4563b..9f8771c 100644
--- a/lib/Parse/ParseStmt.cpp
+++ b/lib/Parse/ParseStmt.cpp
@@ -1240,5 +1240,5 @@
   if (FnBody.isInvalid())
     FnBody = Owned(Actions.ActOnCompoundStmt(L, R, 0, 0, false));
 
-  return Actions.ActOnFinishFunctionBody(Decl, FnBody.release());
+  return Actions.ActOnFinishFunctionBody(Decl, move_convert(FnBody));
 }