Remove setting forward_unbound_keys.

It introduced a lot of unnecessary complexity (e.g. tracking KeyReleases
to their KeyPresses...) for little benefit.

qutebrowser/app.py

@@ -284,7 +284,7 @@ class QuteBrowser(QApplication):
         # config
         self.config.style_changed.connect(style.invalidate_caches)
         for obj in [tabs, completion, self.mainwindow, config.cmd_history,
-                    websettings, kp["normal"], modes.manager]:
+                    websettings, kp["normal"]]:
             self.config.changed.connect(obj.on_config_changed)
 
         # statusbar

qutebrowser/config/configdata.py

@@ -186,10 +186,6 @@ DATA = OrderedDict([
          SettingValue(types.Bool(), "true"),
          "Whether to automatically enter insert mode if an editable element "
          "is focused after page load."),
-
-        ('forward_unbound_keys',
-         SettingValue(types.Bool(), "false"),
-         "Whether to forward unbound keys to the website in normal mode."),
     )),
 
     ('tabbar', sect.KeyValue(

qutebrowser/keyinput/modes.py

@@ -75,7 +75,6 @@ class ModeManager(QObject):
         _handlers: A dictionary of modes and their handlers.
         _mode_stack: A list of the modes we're currently in, with the active
                      one on the right.
-        _forward_unbound_keys: If we should forward unbound keys.
 
     Signals:
         entered: Emitted when a mode is entered.
@@ -94,8 +93,6 @@ class ModeManager(QObject):
         self._handlers = {}
         self.passthrough = []
         self._mode_stack = []
-        self._forward_unbound_keys = config.get('general',
-                                                'forward_unbound_keys')
 
     @property
     def mode(self):
@@ -160,13 +157,6 @@ class ModeManager(QObject):
             raise ValueError("Can't leave normal mode!")
         self.leave(self.mode)
 
-    @pyqtSlot(str, str)
-    def on_config_changed(self, section, option):
-        """Update local setting when config changed."""
-        if (section, option) == ('general', 'forward_unbound_keys'):
-            self._forward_unbound_keys = config.get('general',
-                                                    'forward_unbound_keys')
-
     def eventFilter(self, obj, evt):
         """Filter all events based on the currently set mode.
 
@@ -213,17 +203,11 @@ class ModeManager(QObject):
                 # KeyPress in a non-passthrough mode - call handler and filter
                 # event from widgets (unless unhandled and configured to pass
                 # unhandled events through)
-                logging.debug("KeyPress, calling handler {}".format(handler))
+                logging.debug("KeyPress, calling handler {} and "
+                              "filtering".format(handler))
                 self.key_pressed.emit(evt)
                 handled = handler(evt) if handler is not None else False
-                logging.debug("handled: {}, forward_unbound_keys: {} -> "
-                              "filtering: {}".format(
-                                  handled, self._forward_unbound_keys,
-                                  handled or not self._forward_unbound_keys))
-                if handled or not self._forward_unbound_keys:
-                    return True
-                else:
-                    return False
+                return True
             else:
                 # KeyRelease in a non-passthrough mode - filter event and
                 # ignore it entirely.