We never ended up using these new objects.
Created attachment 96065 [details] Patch
Comment on attachment 96065 [details] Patch Attachment 96065 [details] did not pass cr-mac-ews (chromium): Output: http://queues.webkit.org/results/8772315
Comment on attachment 96065 [details] Patch Yay for deleting code. Looks like WebKit/chromium/src/WebDragData.cpp includes ChromiumDataObjectLegacy.h.
Created attachment 96112 [details] Patch
Committed r88192: <http://trac.webkit.org/changeset/88192>