bitbake: server/process: Fix logging issues where only the first message was displayed

I realised only the first logging message was being displayed in a given
parsing process. The reason turned out to be the UI handler failing
with a "pop from empty list". The default handler was then lost and
no further messages were processed.

Fix this by catching the exception correctly in the connection writer code.

(Bitbake rev: d3e64f64525187f1409531a0bd99df576e627f7f)

Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

bitbake/lib/bb/server/process.py

@@ -756,8 +756,11 @@ class ConnectionWriter(object):
                 process.queue_signals = True
                 self._send(obj)
                 process.queue_signals = False
-                for sig in process.signal_received.pop():
-                    process.handle_sig(sig, None)
+                try:
+                    for sig in process.signal_received.pop():
+                        process.handle_sig(sig, None)
+                except IndexError:
+                    pass
         else:
             self._send(obj)