DBus::asyncCall did not auto disconnect when our applet gets deleted. If plasma gets reset during such an operation we would end up crashing.
There's no need to have wrappers used by one applet. It just adds maintenence burden on everyone else.
This patch replaces the wrapper with calls that don't require string based method names or untyped arguments which is better long term. This also highlighted that the XML file we were using was out of date.