[orca] Ensure we have exactly one voice value when generating current line text

[Joanmarie Diggs <joanied src gnome org>]

commit a927afa8726216662d08d7df0ab2bc10cddcaeb8
Author: Joanmarie Diggs <jdiggs igalia com>
Date:   Wed Apr 8 13:29:49 2020 -0400

    Ensure we have exactly one voice value when generating current line text
    
    A side effect of removing a redundant call to _generateSubstring() in
    _generateCurrentLineText() is that sometimes we had a voice appended
    and sometimes we didn't. The web script's SayAll functionality expects
    there will be a one-string, one-voice utterance.

 src/orca/speech_generator.py | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)
---
diff --git a/src/orca/speech_generator.py b/src/orca/speech_generator.py
index 7f9a6a618..dfd3fca76 100644
--- a/src/orca/speech_generator.py
+++ b/src/orca/speech_generator.py
@@ -1184,7 +1184,9 @@ class SpeechGenerator(generator.Generator):
         if self._script.utilities.shouldVerbalizeAllPunctuation(obj):
             result[0] = self._script.utilities.verbalizeAllPunctuation(result[0])
 
-        result.extend(acss)
+        if len(result) == 1:
+            result.extend(acss)
+
         return result
 
     def _generateDisplayedText(self, obj, **args):