[Caja] Have HostTools runCajoledModuleString give a nice error if the string doesn't ___.loadModule(). (issue1942042)

[kpreid . switchb . org]

Reviewers: jasvir,


Please review this at http://codereview.appspot.com/1942042/show

Affected files:
  M     src/com/google/caja/plugin/host-tools.js


Index: src/com/google/caja/plugin/host-tools.js
===================================================================
--- src/com/google/caja/plugin/host-tools.js    (revision 4234)
+++ src/com/google/caja/plugin/host-tools.js    (working copy)
@@ -89,7 +89,8 @@
         // This is primarily useful when used from caja.js (Caja in an  
iframe),
         // since the host page doesn't have eval of the frame

-        var moduleFunc;
+        var pumpkin = {};
+        var moduleFunc = pumpkin;
         var oldModuleHandler = ___.getNewModuleHandler();
         var newModuleHandler = ___.makeNormalNewModuleHandler();
         newModuleHandler.handle = ___.markFuncFreeze(
@@ -105,6 +106,10 @@
         } finally {
           ___.setNewModuleHandler(oldModuleHandler);
         }
+        if (moduleFunc === pumpkin) {
+          throw new Error("runCajoledModuleString: the provided code did  
not " +
+            "invoke the new module handler");
+        }
         return moduleFunc(imports);
       }