ExpandHelper: Improve one finger expanding forced handling

Instead of force returning false if view is null, setup a boolean
to force it with custom views like hover. Cherry-picked from CM.

Also request disallow intercept on drag started.

Signed-off-by: Carlo Savignano <stevewatersy@gmail.com>
StatusBarView: Avoid unnecessary calls to mHandler.post()

Signed-off-by: Carlo Savignano <stevewatersy@gmail.com>
Signed-off-by: David L.-W. <xD_e-mail@gmx.de>
Themes: Theme immersive mode cling.

Change-Id: I5521b93f69e859c40cfd62eb4a367562200074e9