Add tabindex to default 'all' selector

See #178

doc/help/settings.asciidoc

@@ -2609,6 +2609,7 @@ Default:
 * +pass:[[ngClick]]+
 * +pass:[[data-ng-click]]+
 * +pass:[[x-ng-click]]+
+* +pass:[[tabindex]]+
 - +pass:[images]+:
 
 * +pass:[img]+

qutebrowser/config/configdata.yml

@@ -1186,6 +1186,7 @@ hints.selectors:
       - '[ngClick]'
       - '[data-ng-click]'
       - '[x-ng-click]'
+      - '[tabindex]'
     links:
       - 'a[href]'
       - 'area[href]'

tests/unit/browser/webkit/test_webkitelem.py

@@ -183,6 +183,8 @@ class SelectionAndFilterTests:
         ('<p role="option" foo="bar"/>', ['all']),
         ('<p role="button" foo="bar"/>', ['all']),
         ('<p role="button" href="bar"/>', ['all', 'url']),
+
+        ('<span tabindex=0 />', ['all']),
     ]
 
     GROUPS = ['all', 'links', 'images', 'url', 'inputs']