sstephenson/prototype — pull request #91 by jwestbrook (2012-12-28 22:09:08+00:00)
Title: Added html5data methods set/get

Based on the issue below `sethtml5data()` and `gethtml5data()` will write to
the dataset and the write the data-* attributes correctly in any
browsers that Prototype supports.

https://prototype.lighthouseapp.com/projects/8886/tickets/250-support-for-dataset-property-and-data-attributes