Trebuchet : Activate the default homepage selection button on first run

As of now, when the Trebuchet is started for the first time, the set default 
homepage button is not activated on any of the screens.
Activating it for the first time on default home screen makes more sense.

Change-Id: Ia1b7272e177707616902d20ce90ff6ba293576b4
Signed-off-by: Umair Khan <omerjerk@gmail.com>
(cherry picked from commit d15317d1)