Change active/inactive state spec
"active" state means "visible" on source code currently.
Specification in HMI-FW spec 0.9.2 says it's not visible.
https://wiki.automotivelinux.org/hmiframework
It's the right to have resources such as buffers(surface).
But from the view point of implementation of windowmanager-service,
it is difficult to control resources of application.
So this patch fixes just adding the methods to change
the state of client.
Change-Id: If445af3cdf724827ccf28f40af28cca4a2ffcbc1
Signed-off-by: Kazumasa Mitsunari <knimitz@witz-inc.co.jp>