Description of problem:
On fresh rawhide install with MATE desktop, I installed pitivi and launched it. The pitivi window briefly appeared, then it crashed.

Version-Release number of selected component:
pitivi-0.93-4.fc21

Additional info:
reporter:       libreport-2.2.2
cmdline:        python2 /usr/bin/pitivi
executable:     /usr/bin/pitivi
kernel:         3.15.0-0.rc5.git0.1.fc21.x86_64
runlevel:       N 5
type:           Python
uid:            1000

Truncated backtrace:
project.py:559:__init__:TypeError: function takes at most 0 arguments (1 given)

Traceback (most recent call last):
  File "/usr/bin/pitivi", line 137, in <module>
    _run_pitivi()
  File "/usr/bin/pitivi", line 124, in _run_pitivi
    sys.exit(ptv.main(sys.argv))
  File "/usr/share/pitivi/python/pitivi/application.py", line 416, in main
    ptv = StartupWizardGuiPitivi(debug=options.debug)
  File "/usr/share/pitivi/python/pitivi/application.py", line 362, in __init__
    self.projectManager.newBlankProject(emission=False)
  File "/usr/share/pitivi/python/pitivi/project.py", line 419, in newBlankProject
    project = Project(_("New Project"))
  File "/usr/share/pitivi/python/pitivi/project.py", line 559, in __init__
    Gst.Caps("application/ogg"),
TypeError: function takes at most 0 arguments (1 given)

Local variables in innermost frame:
self: <Project object at 0x3d1ad70 (pitivi+project+Project at 0x401b0e0)>
unused_kwargs: {}
name: 'New Project'
uri: None