[orca] Add sanity check that we have an object before querying its text interface

[Joanmarie Diggs <joanied src gnome org>]

commit 12617a96aa8a9e7b1f4bfb5418058195a0b0eaee
Author: Joanmarie Diggs <jdiggs igalia com>
Date:   Tue Oct 13 19:27:37 2015 -0400

    Add sanity check that we have an object before querying its text interface

 src/orca/scripts/web/script_utilities.py |    3 +++
 1 files changed, 3 insertions(+), 0 deletions(-)
---
diff --git a/src/orca/scripts/web/script_utilities.py b/src/orca/scripts/web/script_utilities.py
index 599475f..7b6a758 100644
--- a/src/orca/scripts/web/script_utilities.py
+++ b/src/orca/scripts/web/script_utilities.py
@@ -630,6 +630,9 @@ class Utilities(script_utilities.Utilities):
         return rv
 
     def queryNonEmptyText(self, obj, excludeNonEntryTextWidgets=True):
+        if not obj:
+            return None
+
         if hash(obj) in self._text:
             return self._text.get(hash(obj))