Unhandled exception

[coffeedogs]

Traceback (most recent call last):                                                                         
  File "/home/coffeedogs/PyBitmessage_codeq31-05/src/bitmessageqt/__init__.py", line 4651, in treeWidgetItemChanged
    self.getCurrentTreeWidget().currentItem() is None,                                                     
AttributeError: 'bool' object has no attribute 'currentItem'

Discovered the above stack trace while working on #1265. Have included fix in branch for same.