[orca] Sanity check text objects for actual text before scrolling substring to point

[Joanmarie Diggs <joanied src gnome org>]

commit 8dd9d2dfea4b981c37213345ba7234065a43b3e8
Author: Joanmarie Diggs <jdiggs igalia com>
Date:   Mon Nov 25 11:17:43 2019 -0500

    Sanity check text objects for actual text before scrolling substring to point

 src/orca/eventsynthesizer.py | 2 ++
 1 file changed, 2 insertions(+)
---
diff --git a/src/orca/eventsynthesizer.py b/src/orca/eventsynthesizer.py
index 418144f2a..e2c0b0556 100644
--- a/src/orca/eventsynthesizer.py
+++ b/src/orca/eventsynthesizer.py
@@ -223,6 +223,8 @@ def _scrollSubstringToLocation(obj, location, startOffset, endOffset):
 
     try:
         text = obj.queryText()
+        if not text.characterCount:
+            return False
         if startOffset is None:
             startOffset = 0
         if endOffset is None: