Add "Make video call" button to search fragments.

= Add new "make video call" shortcut type, and "handle" its click
in SearchFragment.
= Enable "make video call" shortcut for regular and smart dial search
fragments. For now, this shortcut does nothing.
= Enable "add contact" shortcut for smart dial search fragment.
= Changed the bounds of the shortcut items to fill to the edges.
= Convert shortcut click handling to use switch/case block.
= TODO: Enable/disable the shortcuts depending on whether video
calling has been enabled, once the option is available.
= TODO: Handle dispatching a video call intent, once that intent
extra is provided.

Bug: 16013180
Change-Id: I7563d1f2939e27c4b13ed966b73cd4badd9d9fa7