widgets: focus text fields in refspec dialogs

Give focus to the text input fields in the GitRef dialogs that use the
text completion widgets.

Signed-off-by: David Aguilar <davvid@gmail.com>

cola/widgets/completion.py

@@ -664,10 +664,7 @@ def __init__(self, lineedit, title, text, parent, icon=None):
 
         self.label = QtWidgets.QLabel()
         self.label.setText(title)
-
         self.lineedit = lineedit()
-        self.setFocusProxy(self.lineedit)
-
         self.ok_button = qtutils.ok_button(text, icon=icon, enabled=False)
         self.close_button = qtutils.close_button()
 
@@ -685,6 +682,9 @@ def __init__(self, lineedit, title, text, parent, icon=None):
         qtutils.connect_button(self.ok_button, self.accept)
         qtutils.connect_button(self.close_button, self.reject)
 
+        self.setFocusProxy(self.lineedit)
+        self.lineedit.setFocus(True)
+
     def text(self):
         return self.lineedit.text()