Add WEBKIT_SNAPSHOT_OPTIONS_TRANSPARENT_BACKGROUND flag to not fill with white the background before rendering the snapshot.
Created attachment 244899 [details] Patch
Thanks for the patch. If this patch contains new public API please make sure it follows the guidelines for new WebKit2 GTK+ API. See http://trac.webkit.org/wiki/WebKitGTK/AddingNewWebKit2API
Comment on attachment 244899 [details] Patch Looks good to me. Needs one more reviewer though.
Comment on attachment 244899 [details] Patch Yep!
Committed r178700: <http://trac.webkit.org/changeset/178700>