Replace the existing input event handler in tests with 'InputEventHandlerSlot'
Replace the existing input event handler in tests with 'InputEventHandlerSlot'

ruleless/CEGUI,ruleless/CEGUI,OpenTechEngine/CEGUI,OpenTechEngine/CEGUI,ruleless/CEGUI,OpenTechEngine/CEGUI,ruleless/CEGUI,OpenTechEngine/CEGUI