Adds an interface for the KeyguardExternalViewProviderService to
communicate with the host in SystemUI. This includes handling
notifying the host when the provider service has died.
Change-Id: Icd185da289913b84da09707f1d8a2f4f4ff86bae
KeyguardExternalView requires extra state callbacks that can be passed
on to the KeyguardExternalViewProvider. For this reason the
KeyguardExternalViewProvider no longer extends ExternalViewProvider
and instead provides the full implementation needed for ExternalViews
as well as the specific keyguard components.
Change-Id: Icf3589a201bf0ab29ba6e00e2bd6c0149e955e1d
Danesh M