/**
* Starts a background thread to process contact-lookup requests, unless one has already been
* started.
*/
private synchronized void startRequestProcessing() {
// For unit-testing.
if (mRequestProcessingDisabled) return;
// Idempotence... if a thread is already started, don't start another.
if (mCallerIdThread != null) return;
mCallerIdThread = new QueryThread();
mCallerIdThread.setPriority(Thread.MIN_PRIORITY);
mCallerIdThread.start();
}
