[orca] Use isDocument method when looking for documentFrame

[Joanmarie Diggs <joanied src gnome org>]

commit 9effa6fc4afaa6a2ce8134adc5080a9c49af6995
Author: Joanmarie Diggs <jdiggs igalia com>
Date:   Fri Oct 23 00:29:02 2015 -0400

    Use isDocument method when looking for documentFrame

 src/orca/scripts/web/script_utilities.py |    4 +---
 1 files changed, 1 insertions(+), 3 deletions(-)
---
diff --git a/src/orca/scripts/web/script_utilities.py b/src/orca/scripts/web/script_utilities.py
index 78733b0..b1faadf 100644
--- a/src/orca/scripts/web/script_utilities.py
+++ b/src/orca/scripts/web/script_utilities.py
@@ -181,9 +181,7 @@ class Utilities(script_utilities.Utilities):
         if not targets:
             return []
 
-        roles = [pyatspi.ROLE_DOCUMENT_FRAME, pyatspi.ROLE_DOCUMENT_WEB]
-        isDocument = lambda x: x and x.getRole() in roles
-        return list(filter(isDocument, targets))
+        return list(filter(self.isDocument, targets))
 
     def documentFrame(self, obj=None):
         isShowing = lambda x: x and x.getState().contains(pyatspi.STATE_SHOWING)