Sketch of Native input for MessageQueue / Looper / ViewRoot

MessageQueue now uses a socket for internal signalling, and is prepared
to also handle any number of event input pipes, once the plumbing is
set up with ViewRoot / Looper to tell it about them as appropriate.

Change-Id: If9eda174a6c26887dc51b12b14b390e724e73ab3
7 files changed