Comment 4 for bug 910713

Exception during installation:
 Jan 2 17:24:39 ubuntu plugininstall.py: Traceback (most recent call last):
 Jan 2 17:24:39 ubuntu plugininstall.py: File "/usr/share/ubiquity/plugininstall.py", line 1641, in <module>
 Jan 2 17:24:39 ubuntu plugininstall.py: install.run()
 Jan 2 17:24:39 ubuntu plugininstall.py: File "/usr/share/ubiquity/plugininstall.py", line 55, in wrapper
 Jan 2 17:24:39 ubuntu plugininstall.py: func(self)
 Jan 2 17:24:39 ubuntu plugininstall.py: File "/usr/share/ubiquity/plugininstall.py", line 182, in run
 Jan 2 17:24:39 ubuntu plugininstall.py: self.configure_hardware()
 Jan 2 17:24:39 ubuntu plugininstall.py: File "/usr/share/ubiquity/plugininstall.py", line 840, in configure_hardware
 Jan 2 17:24:39 ubuntu plugininstall.py: install_misc.chroot_setup(self.target, x11=True)
 Jan 2 17:24:39 ubuntu plugininstall.py: File "/usr/lib/ubiquity/ubiquity/install_misc.py", line 155, in chroot_setup
 Jan 2 17:24:39 ubuntu plugininstall.py: os.path.join(target, 'root/.Xauthority'))
 Jan 2 17:24:39 ubuntu plugininstall.py: File "/usr/lib/python2.7/shutil.py", line 116, in copy
 Jan 2 17:24:39 ubuntu plugininstall.py: copyfile(src, dst)
 Jan 2 17:24:39 ubuntu plugininstall.py: File "/usr/lib/python2.7/shutil.py", line 81, in copyfile
 Jan 2 17:24:39 ubuntu plugininstall.py: with open(src, 'rb') as fsrc:
 Jan 2 17:24:39 ubuntu plugininstall.py: IOError: [Errno 21] Is a directory: '/home/ubuntu/.Xauthority'
 Jan 2 17:24:39 ubuntu plugininstall.py: