This error message can appear in the logcat, at least in version 2.0 I saw it first in bug 1050751 I traced it to app.js:200. The dragdrop module is lazy loaded, so it is possible for that code to run before the dragdrop property is defined. This is pretty obviously just a case where you need to test for its existance before using it. I can reproduce the error by launching an app, using adb shell kill to kill the homescreen and then rapidly tapping multiple times on the home button. This launches a new homescreen and then triggers that app.js:200 code before the lazy load is done. _grid.dragdrop is also used without checking in the context menu code, but I didn't try to cause an error there.
This should not cause any problems, but we should definitely fix it. Thanks for filing.
Created attachment 8470307 [details] [review] Github pull request David - any chance you'd be willing to throw a review stamp on this since you reported it? :)
Comment on attachment 8470307 [details] [review] Github pull request Hey Chris - any chance you have some cycles for a review? Thanks!
[Blocking Requested - why for this release]: This is needed to help us solve bug 1048639 (a CAF blocker).
Comment on attachment 8470307 [details] [review] Github pull request LGTM + points for test :)
Comment on attachment 8470307 [details] [review] Github pull request This looks good to me. I've noted a few nits on github, but nothing that I feel needs to be fixed. Consider adding a similar fix in the contextmenu event case in contextmenu_handler.js before landing.
See comment 4
Comment on attachment 8470307 [details] [review] Github pull request Thanks for the review guys. I'm making some minor updates to the code based on David's comments and will land this.