[orca] Chromium: Handle list item markers which lack "::marker" tag

[Joanmarie Diggs <joanied src gnome org>]

commit 9bd079f95b430aac31bc6c03d324048768393b61
Author: Joanmarie Diggs <jdiggs igalia com>
Date:   Fri Feb 28 13:46:34 2020 +0100

    Chromium: Handle list item markers which lack "::marker" tag

 src/orca/scripts/toolkits/Chromium/script_utilities.py | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)
---
diff --git a/src/orca/scripts/toolkits/Chromium/script_utilities.py 
b/src/orca/scripts/toolkits/Chromium/script_utilities.py
index 168d83ee3..7dfc21a0f 100644
--- a/src/orca/scripts/toolkits/Chromium/script_utilities.py
+++ b/src/orca/scripts/toolkits/Chromium/script_utilities.py
@@ -99,7 +99,10 @@ class Utilities(web.Utilities):
         if rv is not None:
             return rv
 
-        rv = self._getTag(obj) == "::marker" and obj.parent.getRole() == pyatspi.ROLE_LIST_ITEM
+        rv = False
+        if obj.parent.getRole() == pyatspi.ROLE_LIST_ITEM:
+            rv = self._getTag(obj) in ["::marker", None] and obj.parent[0] == obj
+
         self._isListItemMarker[hash(obj)] = rv
         return rv