move part of the logic to TabbedBrowser

qutebrowser/mainwindow/tabbedbrowser.py

@@ -577,3 +577,12 @@ class TabbedBrowser(tabwidget.TabWidget):
         """
         super().resizeEvent(e)
         self.resized.emit(self.geometry())
+
+    def wheelEvent(self, e):
+        """Override wheelEvent of QWidget to forward it to the focused tab.
+
+        Args:
+            e: The QWheelEvent
+        """
+        if self._now_focused is not None:
+            self._now_focused.wheelEvent(e)

qutebrowser/mainwindow/tabwidget.py

@@ -480,16 +480,18 @@ class TabBar(QTabBar):
             new_idx = super().insertTab(idx, icon, '')
         self.set_page_title(new_idx, text)
 
-    def wheelEvent(self, event):
+    def wheelEvent(self, e):
-        """Override wheelEvent to make the action configurable."""
+        """Override wheelEvent to make the action configurable.
+
+        Args:
+            e: The QWheelEvent
+        """
         if config.get('tabs', 'mousewheel-tab-switching'):
-            super().wheelEvent(event)
+            super().wheelEvent(e)
         else:
             tabbed_browser = objreg.get('tabbed-browser', scope='window',
                                         window=self._win_id)
-            focused_tab = tabbed_browser.currentWidget()
+            tabbed_browser.wheelEvent(e)
-            if focused_tab is not None:
-                focused_tab.wheelEvent(event)
 
 
 class TabBarStyle(QCommonStyle):