Turn webspeech on/off when tab goes fore/background

content/renderer/speech_recognition_dispatcher.cc

Index: content/renderer/speech_recognition_dispatcher.cc
diff --git a/content/renderer/speech_recognition_dispatcher.cc b/content/renderer/speech_recognition_dispatcher.cc
index 3d76c20b90825a495e7da382468866f87e26a8b4..178abf4610c286c751047ff46ec252089f2946bb 100644
--- a/content/renderer/speech_recognition_dispatcher.cc
+++ b/content/renderer/speech_recognition_dispatcher.cc
@@ -35,6 +35,11 @@ SpeechRecognitionDispatcher::SpeechRecognitionDispatcher(
 SpeechRecognitionDispatcher::~SpeechRecognitionDispatcher() {
 }
 
+void SpeechRecognitionDispatcher::AbortAllRecognitions() {
+  Send(new SpeechRecognitionHostMsg_AbortAllRequests(
+      routing_id()));
+}
+
 bool SpeechRecognitionDispatcher::OnMessageReceived(
     const IPC::Message& message) {
   bool handled = true;