Fix mute_per_domain feature

Users can allow sounds to be played by
default while specifying domains not allowed
to play sounds, or the opposite.

qutebrowser/browser/webengine/webenginetab.py

@@ -653,9 +653,9 @@ class WebEngineAudio(browsertab.AbstractAudio):
         return page.recentlyAudible()
 
     def _on_url_changed(self):
-        urlstr = self._tab.url().toString(QUrl.RemoveUserInfo)
-        muted_url = config.instance.get('content.mute', url=urlstr)
-        self.set_muted(muted_url is not None)
+        url = self._tab.url()
+        is_audible = config.instance.get('content.audible_default', url=url)
+        self.set_muted(not is_audible)
 
 
 class _WebEnginePermissions(QObject):

qutebrowser/config/configdata.yml

@@ -746,13 +746,11 @@ content.xss_auditing:
     Suspicious scripts will be blocked and reported in the inspector's
     JavaScript console.
 
-content.mute:
-  default: null
-  type:
-    name: String
-    none_ok: true
+content.audible_default:
+  default: true
+  type: Bool
+  desc: Play sounds automatically in web pages.
   supports_pattern: true
-  desc: List of URLs muted by default.
 
 # emacs: '