This patch finally fixes bug 827888 were a message's reply was
received before the respective handler function could be installed.
The patch adds the class DBusConnectionSendWithReplyTask, which
asyncronously sends a DBus message and installs the reply's handler
function. The DBus utility functions for asyncronous messages create
an instance of this class and dispatch it to the DBus thread. This
intercepts the DBusPollTask, so no DBus replies can be received until
the dispatched DBusConnectionSendWithReplyTask has finished.
If a DBUS call completes before we can set the notifier function, the
call's response never gets handled. To workaround this problem, we now
call the notifier explicitly if the call completes this early.
It can still happen that the call's response gets lost, but this
workaround greatly improves the success rate for our problem of handling
errors during Bluetooth device pairing; from maybe 10% to 75%.
Thomas Zimmermann
Gina Yeh
Kyle Machulis
Eric Chou
Ryan VanderMeulen
Ms2ger