[orca] Handle yet another object going defunct on us

[Joanmarie Diggs <joanied src gnome org>]

commit 3d4ba44462d5d3ef531236d95f8a70b2ea317fd7
Author: Joanmarie Diggs <jdiggs igalia com>
Date:   Thu Apr 25 07:36:58 2019 -0400

    Handle yet another object going defunct on us

 src/orca/scripts/web/script_utilities.py | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)
---
diff --git a/src/orca/scripts/web/script_utilities.py b/src/orca/scripts/web/script_utilities.py
index 61a45a62c..edea1b074 100644
--- a/src/orca/scripts/web/script_utilities.py
+++ b/src/orca/scripts/web/script_utilities.py
@@ -3752,8 +3752,11 @@ class Utilities(script_utilities.Utilities):
         if self.isDocument(obj):
             return
 
-        for child in obj:
-            self.clearTextSelection(child)
+        try:
+            for child in obj:
+                self.clearTextSelection(child)
+        except:
+            pass
 
     def clearCaretContext(self, documentFrame=None):
         self.clearContentCache()