[orca] Have popupType return False as a string to be consistent with ARIA values

[Joanmarie Diggs <joanied src gnome org>]

commit 8368b43010fee0e6f1cec9a8bc8072ba9244eec4
Author: Joanmarie Diggs <jdiggs igalia com>
Date:   Wed Oct 9 13:42:49 2019 -0400

    Have popupType return False as a string to be consistent with ARIA values

 src/orca/scripts/web/script_utilities.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
---
diff --git a/src/orca/scripts/web/script_utilities.py b/src/orca/scripts/web/script_utilities.py
index 8860365b8..1c4c2d69e 100644
--- a/src/orca/scripts/web/script_utilities.py
+++ b/src/orca/scripts/web/script_utilities.py
@@ -3534,7 +3534,7 @@ class Utilities(script_utilities.Utilities):
 
     def popupType(self, obj):
         if not (obj and self.inDocumentContent(obj)):
-            return False
+            return 'false'
 
         rv = self._popupType.get(hash(obj))
         if rv is not None: