Completed the patch for Bug #215126.
* Fixes an incorrect variable in a PyDict_CheckExact.
* Allow general mapping locals arguments for the execfile() function
  and exec statement.
* Add tests.
diff --git a/Misc/NEWS b/Misc/NEWS
index 15713e9..edd5989 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -269,7 +269,8 @@
 - Bug #951851: Python crashed when reading import table of certain
   Windows DLLs.
 
-- Bug #215126.  The locals argument to eval() now accepts any mapping type.
+- Bug #215126.  The locals argument to eval(), execfile(), and exec now
+  accept any mapping type.
 
 - marshal now shares interned strings. This change introduces
   a new .pyc magic.