[orca] Add sanity check before getting role of object

[Joanmarie Diggs <joanied src gnome org>]

commit 6c9aaefa4381b333f0a54fb34cdfd0697ae51136
Author: Joanmarie Diggs <jdiggs igalia com>
Date:   Fri Feb 8 15:03:59 2019 -0500

    Add sanity check before getting role of object

 src/orca/scripts/web/script.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
---
diff --git a/src/orca/scripts/web/script.py b/src/orca/scripts/web/script.py
index d83975135..69bbdd6ab 100644
--- a/src/orca/scripts/web/script.py
+++ b/src/orca/scripts/web/script.py
@@ -782,7 +782,7 @@ class Script(default.Script):
             debug.println(debug.LEVEL_INFO, msg, True)
             return True
 
-        if self._inFocusMode and obj.getRole() == pyatspi.ROLE_RADIO_BUTTON:
+        if self._inFocusMode and obj and obj.getRole() == pyatspi.ROLE_RADIO_BUTTON:
             msg = "WEB: Staying in focus mode due to role of %s" % obj
             debug.println(debug.LEVEL_INFO, msg, True)
             return True