widget: set the correct default value for tooltip-text
widget: set the correct default value for tooltip-text

Set the correct default value in the property specification of the
tooltip-text property.

pwithnall/mx,jonnylamb/mx,clutter-project/mx,clutter-project/mx,pwithnall/mx,pwithnall/mx,jonnylamb/mx,clutter-project/mx,jonnylamb/mx,clutter-project/mx,pwithnall/mx,jonnylamb/mx