Fix raising of WebTabError

qutebrowser/browser/webkit/webelem.py

@@ -533,5 +533,3 @@ def focus_elem(frame):
     """
     elem = frame.findFirstElement(SELECTORS[Group.focus])
     return WebElementWrapper(elem)
-
-

qutebrowser/browser/webkit/webkittab.py

@@ -560,7 +560,7 @@ class WebKitTab(browsertab.AbstractTab):
     def find_all_elements(self, selector, *, only_visible=False):
         mainframe = self._widget.page().mainFrame()
         if mainframe is None:
-            raise WebTabError("No frame focused!")
+            raise browsertab.WebTabError("No frame focused!")
 
         elems = []
         frames = webelem.get_child_frames(mainframe)