Allows endCallbacks in tts to queue up speech in the speech queue and simplify speech output logic.

chrome/browser/resources/chromeos/chromevox/chromevox/background/background.js

Index: chrome/browser/resources/chromeos/chromevox/chromevox/background/background.js
diff --git a/chrome/browser/resources/chromeos/chromevox/chromevox/background/background.js b/chrome/browser/resources/chromeos/chromevox/chromevox/background/background.js
index 21682f724433dccbc9109ebbb9d8c2a668c95314..daad1a489330bc8409ca584dbbbf5abb65dbaea3 100644
--- a/chrome/browser/resources/chromeos/chromevox/chromevox/background/background.js
+++ b/chrome/browser/resources/chromeos/chromevox/chromevox/background/background.js
@@ -381,14 +381,16 @@ cvox.ChromeVoxBackground.prototype.addBridgeListener = function() {
       break;
     case 'TTS':
       if (msg['startCallbackId'] != undefined) {
-        msg['properties']['startCallback'] = function() {
+        msg['properties']['startCallback'] = function(opt_cleanupOnly) {
           port.postMessage({'message': 'TTS_CALLBACK',
+                            'cleanupOnly': opt_cleanupOnly,
                             'id': msg['startCallbackId']});
         };
       }
       if (msg['endCallbackId'] != undefined) {
-        msg['properties']['endCallback'] = function() {
+        msg['properties']['endCallback'] = function(opt_cleanupOnly) {
           port.postMessage({'message': 'TTS_CALLBACK',
+                            'cleanupOnly': opt_cleanupOnly,
                             'id': msg['endCallbackId']});
         };
       }