I get this error when JS aggregation is enabled, as is jquery_update (no updating on Aurora's side).
Can you please let me know what version you are using, as well as the settings for putting the JS in the footer, and if you are using the experimental handling.
I have just made some changes, and the code seems to be working on my site... but that is a limited use case.
I just had this error and ran through it with xdebug.
This is most likely because you don't have the actual Modernizr JS library installed in either your module folder (sites/*/modules/modernizr/js/modernizr-min.js) or library folder (sites/all/libraries/modernizr/modernizr.min.js).
The function modernizr_get_path() looks in the module & libraries folders for the '/^modernizr[a-z0-9\.-]*\.js$/' file.
To solve you could grab http://modernizr.com/downloads/modernizr-latest.js and put in your Modernizr module folder, like this => sites/*/modules/modernizr/js/modernizr-min.js
Crosslinking similar issue - http://drupal.org/node/1862860
This error has not been since since that version-- and updates to Aurora / Modernizr seem to have fixed it.
Just to clarify from #3 above, should this be modernizr-min.js or modernizr.min.js, as is stated on http://drupal.org/project/modernizr?
It is "modernizr.min.js", all future questions should refer to the modernizr module's docs.
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