Merge ~arraybolt3/software-properties:ubuntu/master into software-properties:ubuntu/master

[Aaron Rainbolt]

Stop using KUrl and KFileDialog

KUrl and KFileDialog both no longer are available to
software-properties-qt, but were used for the "Import Key File..."
button in the Authentication tab. This caused the button to break.
Removing the KUrl-related line and switching from KFileDialog to
QFileDialog resolves this problem. (LP: #1795278)

diff --git a/softwareproperties/qt/SoftwarePropertiesQt.py b/softwareproperties/qt/SoftwarePropertiesQt.py
index 93eb687..90b8d5a 100644
--- a/softwareproperties/qt/SoftwarePropertiesQt.py
+++ b/softwareproperties/qt/SoftwarePropertiesQt.py
@@ -718,8 +718,10 @@ class SoftwarePropertiesQt(SoftwareProperties):
     home = QDir.homePath()
     if "SUDO_USER" in os.environ:
         home = os.path.expanduser("~%s" % os.environ["SUDO_USER"])
-    url = KUrl.fromPath(home)
-    filename = KFileDialog.getOpenFileName(url, 'application/pgp-keys', self.userinterface, _("Import key"))
+    filename = QFileDialog.getOpenFileName(self.userinterface,
+                                           _("Import key"),
+                                           home,
+                                           _("GPG key file (*.gpg)"))[0]
     if filename:
       if not self.add_key(filename):
         title = _("Error importing selected file")