Remove MouseLock permission support

For some reason it doesn't work...

doc/help/settings.asciidoc

@@ -161,7 +161,6 @@
 |<<content-geolocation,geolocation>>|Allow websites to request geolocations.
 |<<content-notifications,notifications>>|Allow websites to show notifications.
 |<<content-media-capture,media-capture>>|Allow websites to record audio/video.
-|<<content-mouse-lock,mouse-lock>>|Allow websites to lock the mouse pointer.
 |<<content-javascript-can-open-windows-automatically,javascript-can-open-windows-automatically>>|Whether JavaScript programs can open new windows without user interaction.
 |<<content-javascript-can-close-windows,javascript-can-close-windows>>|Whether JavaScript programs can close windows.
 |<<content-javascript-can-access-clipboard,javascript-can-access-clipboard>>|Whether JavaScript programs can read or write to the clipboard.
@@ -1466,20 +1465,6 @@ Default: +pass:[ask]+
 
 This setting is only available with the QtWebEngine backend.
 
-[[content-mouse-lock]]
-=== mouse-lock
-Allow websites to lock the mouse pointer.
-
-Valid values:
-
- * +true+
- * +false+
- * +ask+
-
-Default: +pass:[ask]+
-
-This setting is only available with the QtWebEngine backend.
-
 [[content-javascript-can-open-windows-automatically]]
 === javascript-can-open-windows-automatically
 Whether JavaScript programs can open new windows without user interaction.

qutebrowser/browser/webengine/webview.py

@@ -133,7 +133,6 @@ class WebEnginePage(QWebEnginePage):
             QWebEnginePage.MediaAudioCapture: ('content', 'media-capture'),
             QWebEnginePage.MediaVideoCapture: ('content', 'media-capture'),
             QWebEnginePage.MediaAudioVideoCapture: ('content', 'media-capture'),
-            QWebEnginePage.MouseLock: ('content', 'mouse-lock'),
         }
         messages = {
             QWebEnginePage.Geolocation: 'access your location',
@@ -141,6 +140,15 @@ class WebEnginePage(QWebEnginePage):
             QWebEnginePage.MediaVideoCapture: 'record video',
             QWebEnginePage.MediaAudioVideoCapture: 'record audio/video',
         }
+        assert options.keys() == messages.keys()
+
+        if feature not in options:
+            log.webview.error("Unhandled feature permission {}".format(
+                debug.qenum_key(QWebEnginePage, feature)))
+            self.setFeaturePermission(url, feature,
+                                      QWebEnginePage.PermissionDeniedByUser)
+            return
+
         yes_action = functools.partial(
             self.setFeaturePermission, url, feature,
             QWebEnginePage.PermissionGrantedByUser)

qutebrowser/config/configdata.py

@@ -826,11 +826,6 @@ def data(readonly=False):
                           backends=[usertypes.Backend.QtWebEngine]),
              "Allow websites to record audio/video."),
 
-            ('mouse-lock',
-             SettingValue(typ.BoolAsk(), 'ask',
-                          backends=[usertypes.Backend.QtWebEngine]),
-             "Allow websites to lock the mouse pointer."),
-
             ('javascript-can-open-windows-automatically',
              SettingValue(typ.Bool(), 'false'),
              "Whether JavaScript programs can open new windows without user "