Make 'module' a context-sensitive keyword.

test/mjsunit/harmony/module-parsing.js

 // Copyright 2011 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 45 matching lines @@
 module D2 = C1.D
 module D3 = D2
 
 module E1 at "http://where"
 module E2 at "http://where";
 module E3 = E1.F
 
 
 // Check that ASI does not interfere.
 
-module
-X
+module X
 {
 let x
 }
 
-module
-Y
+module Y
 =
 X
 
-module
-Z
+module Z
 at
 "file://local"
+
+
+// Check that 'module' still works as an identifier.
+
+var module
+module = {}
+module["a"] = 6
+function module() {}
+function f(module) { return module }
+try {} catch (module) {}
+
+module
+v = 20