Fix property change handler in InteractionJankMonitor.

The property change handler is provided with a property map that only
contains the properties that have changed, not all the properties in
our namespace. The old verison would reset properties back to their
default, whenever a property change event was received without the full
list of properties.

Test: manual
Change-Id: I37fa747c0873d332db84c777638203638c60c127