Have the mock PlatformSpeechSynthesizer ignore pause/resume sometimes.

third_party/WebKit/Source/modules/speech/testing/PlatformSpeechSynthesizerMock.cpp

 /*
  * Copyright (C) 2013 Apple Computer, Inc.  All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 103 matching lines @@
 
     // Per spec, removes all queued utterances.
     m_queuedUtterances.clear();
 
     m_speakingFinishedTimer.stop();
     m_speakingErrorOccurredTimer.startOneShot(.1, BLINK_FROM_HERE);
 }
 
 void PlatformSpeechSynthesizerMock::pause()
 {
+    if (!m_currentUtterance)
+        return;
+
     client()->didPauseSpeaking(m_currentUtterance);
 }
 
 void PlatformSpeechSynthesizerMock::resume()
 {
+    if (!m_currentUtterance)
+        return;
+
     client()->didResumeSpeaking(m_currentUtterance);
 }
 
 DEFINE_TRACE(PlatformSpeechSynthesizerMock)
 {
     visitor->trace(m_currentUtterance);
     visitor->trace(m_queuedUtterances);
     PlatformSpeechSynthesizer::trace(visitor);
 }
 
 } // namespace blink