- Extend the dismiss timeout when interacting with various
subcontrols.
- Ensure "hover" events in touch exploration extend the timeout
in addition to touch events.
- Introduce new helper to standardize interaction callbacks.
- Announce zen toasts.
- Announce zen condition selections, and when existing countdown
conditions are modified.
Bug:17578434
Change-Id: I8a055b3455aa8d20ba93439bdec6cc75db97800e