Make the strict-mode calling convention for contextual calls the default one.

test/mjsunit/harmony/object-observe.js

Index: test/mjsunit/harmony/object-observe.js
diff --git a/test/mjsunit/harmony/object-observe.js b/test/mjsunit/harmony/object-observe.js
index 72a9cadbf8ecb9df05a37593055e58e3c44f7efc..fb15a1fa835a06f5211f880938dbe1be03901c57 100644
--- a/test/mjsunit/harmony/object-observe.js
+++ b/test/mjsunit/harmony/object-observe.js
@@ -147,8 +147,9 @@ assertThrows(function() { notifier.performChange(1, function(){}); }, TypeError)
 assertThrows(function() { notifier.performChange(undefined, function(){}); }, TypeError);
 assertThrows(function() { notifier.performChange('foo', undefined); }, TypeError);
 assertThrows(function() { notifier.performChange('foo', 'bar'); }, TypeError);
+var global = this;
 notifier.performChange('foo', function() {
-  assertEquals(undefined, this);
+  assertEquals(global, this);
 });
 
 var notify = notifier.notify;