During testing I've noticed Sandbox Violations being generated for multitouch operations on supported trackpads.
The sandbox should be relaxed to allow the WebProcess to access these IOKit properties:
Created attachment 308433 [details]
Comment on attachment 308433 [details]
I wonder if it's going to be practical to maintain such a fine-grained list going forward.
Committed r215899: <http://trac.webkit.org/changeset/215899>