[orca] Only insert pause character after alphanumeric strings

[Joanmarie Diggs <joanied src gnome org>]

commit 08b587877b6cc56fdc687aeb69db9f748207ae34
Author: Joanmarie Diggs <jdiggs igalia com>
Date:   Tue Mar 27 12:11:52 2018 -0400

    Only insert pause character after alphanumeric strings

 src/orca/speech.py |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/src/orca/speech.py b/src/orca/speech.py
index b21e451..f8cfb23 100644
--- a/src/orca/speech.py
+++ b/src/orca/speech.py
@@ -208,7 +208,7 @@ def speak(content, acss=None, interrupt=True):
             newVoice = ACSS(acss)
             newItemsToSpeak = []
             if isinstance(element, speech_generator.Pause):
-                if not toSpeak[-1].endswith('.'):
+                if toSpeak[-1] and toSpeak[-1][-1].isalnum():
                     toSpeak[-1] += '.'
             elif isinstance(element, ACSS):
                 newVoice.update(element)