Tell the YUI drag/drop delegate that the show/hide and dock icons are not valid drag handles. Otherwise, a drag can be initiated by showing or hiding a block (probably not from docking one, but better safe than sorry). Not strictly related to MDL-34328, but likely to be encountered whilst testing - and closely related to another patch for MDL-34328.
Note that the "invalid" config option for the delegate takes a string - not an array - but can have multiple selectors separated by commas.
Paul Nicholls
3f6970bf92