completion: Use textEdited instead of textChanged

This gets rid of _ignore_next and some unneeded logic, since textEdited
won't even emit if we edited it programatically.

qutebrowser/app.py

@@ -312,7 +312,7 @@ class QuteBrowser(QApplication):
         cmd.clear_completion_selection.connect(
             completion.on_clear_completion_selection)
         cmd.hide_completion.connect(completion.hide)
-        cmd.textChanged.connect(completion.on_cmd_text_changed)
+        cmd.textEdited.connect(completion.on_cmd_text_changed)
         completion.change_completed_part.connect(cmd.on_change_completed_part)
 
     def _recover_pages(self):

qutebrowser/widgets/_completion.py

@@ -59,7 +59,6 @@ class CompletionView(QTreeView):
         _model: The currently active filter model.
         _lastmodel: The model set in the last iteration.
         _completion_models: dict of available completion models.
-        _ignore_next: Whether to ignore the next cmd_text_changed signal.
         _enabled: Whether showing the CompletionView is enabled.
         _completing: Whether we're currently completing something.
         _height: The height to use for the CompletionView.
@@ -124,7 +123,6 @@ class CompletionView(QTreeView):
                                               opt, self)))
                 except NoCompletionsError:
                     pass
-        self._ignore_next = False
         self._completing = False
 
         self._delegate = _CompletionItemDelegate(self)
@@ -219,7 +217,6 @@ class CompletionView(QTreeView):
             QItemSelectionModel.Rows)
         data = self._model.data(idx)
         if data is not None:
-            self._ignore_next = True
             self.change_completed_part.emit(data)
 
     def set_model(self, model):
@@ -254,11 +251,6 @@ class CompletionView(QTreeView):
             text: The new text
         """
         # FIXME we should also consider the cursor position
-        if self._ignore_next:
-            # Text changed by a completion, so we don't have to complete again.
-            self._ignore_next = False
-            return
-
         if not text.startswith(':'):
             # This is a search or gibberish, so we don't need to complete
             # anything (yet)