Handle ampersands in tab titles correctly.

Fixes #301.

qutebrowser/widgets/tabbedbrowser.py

@@ -459,7 +459,7 @@ class TabbedBrowser(tabwidget.TabWidget):
             # We can get signals for tabs we already deleted...
             log.webview.debug("Got invalid tab {}!".format(tab))
             return
-        self.setTabText(idx, text)
+        self.setTabText(idx, text.replace('&', '&&'))
         if idx == self.currentIndex():
             self._change_app_title(text)
 

qutebrowser/widgets/tabwidget.py

@@ -343,9 +343,8 @@ class TabBarStyle(QCommonStyle):
                               else QIcon.Off)
                 icon = opt.icon.pixmap(opt.iconSize, icon_mode, icon_state)
                 p.drawPixmap(icon_rect.x(), icon_rect.y(), icon)
-            self._style.drawItemText(p, text_rect,
-                                     Qt.AlignLeft | Qt.AlignVCenter,
-                                     opt.palette,
+            alignment = Qt.AlignLeft | Qt.AlignVCenter | Qt.TextHideMnemonic
+            self._style.drawItemText(p, text_rect, alignment, opt.palette,
                                      opt.state & QStyle.State_Enabled,
                                      opt.text, QPalette.WindowText)
         else: