Bug crossbario#2096 memory leak in dealer.py

(cherry picked from commit 2b8ae44)

crossbar/router/dealer.py

@@ -40,6 +40,7 @@ class InvocationRequest(object):
  'id',
  'registration',
  'caller',
+ 'caller_session_id',
  'call',
  'callee',
  'forward_for',
@@ -53,6 +54,7 @@ def __init__(self, id, registration, caller, call, callee, forward_for, authoriz
  self.id = id
  self.registration = registration
  self.caller = caller
+ self.caller_session_id = caller._session_id
  self.call = call
  self.callee = callee
  self.forward_for = forward_for
@@ -1132,11 +1134,7 @@ def _remove_invoke_request(self, invocation_request):
 
  del self._invocations[invocation_request.id]
 
- # the session_id will be None if the caller session has
- # already vanished
- caller_id = invocation_request.caller._session_id
- if caller_id is not None:
- del self._invocations_by_call[caller_id, invocation_request.call.request]
+ del self._invocations_by_call[invocation_request.caller_session_id, invocation_request.call.request]
 
  # noinspection PyUnusedLocal
  def processCancel(self, session, cancel):