Add Pause and Resume to Web TTS & Extension TTS APIs

chrome/common/extensions/api/tts.json

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 [
   {
     "namespace": "tts",
     "types": [
       {
         "id": "TtsEvent",
         "type": "object",
         "description": "An event from the TTS engine to communicate the status of an utterance.",
         "properties": {
           "type": {
             "type": "string",
-            "enum": ["start", "end", "word", "sentence", "marker", "interrupted", "cancelled", "error"],
-            "description": "The type can be 'start' as soon as speech has started, 'word' when a word boundary is reached, 'sentence' when a sentence boundary is reached, 'marker' when an SSML mark element is reached, 'end' when the end of the utterance is reached, 'interrupted' when the utterance is stopped or interrupted before reaching the end, 'cancelled' when it's removed from the queue before ever being synthesized, or 'error' when any other error occurs."
+            "enum": ["start", "end", "word", "sentence", "marker", "interrupted", "cancelled", "error", "pause", "resume"],
+            "description": "The type can be 'start' as soon as speech has started, 'word' when a word boundary is reached, 'sentence' when a sentence boundary is reached, 'marker' when an SSML mark element is reached, 'end' when the end of the utterance is reached, 'interrupted' when the utterance is stopped or interrupted before reaching the end, 'cancelled' when it's removed from the queue before ever being synthesized, or 'error' when any other error occurs. When pausing speech, a 'pause' event is fired if a particular utterance is paused in the middle, and 'resume' if an utterance resumes speech. Note that pause and resume events may not fire if speech is paused in-between utterances."
           },
           "charIndex": {
             "type": "number",
             "optional": true,
             "description": "The index of the current character in the utterance."
           },
           "errorMessage": {
             "type": "string",
             "description": "The error description, if the event type is 'error'.",
             "optional": true
@@ skipping 142 matching lines @@
             "name": "callback",
             "optional": true,
             "description": "Called right away, before speech finishes. Check chrome.runtime.lastError to make sure there were no errors. Use options.onEvent to get more detailed feedback.",
             "parameters": []
           }
         ]
       },
       {
         "name": "stop",
         "type": "function",
-        "description": "Stops any current speech.",
+        "description": "Stops any current speech and flushes the queue of any pending utterances. In addition, if speech was paused, it will now be un-paused for the next call to speak.",
         "parameters": []
       },
       {
+        "name": "pause",
+        "type": "function",
+        "description": "Pauses speech synthesis, potentially in the middle of an utterance. A call to resume or stop will un-pause speech.",

[David Tseng, 2013/05/20 17:44:19]

Should speak also unpause speech?

+        "parameters": []
+      },
+      {
+        "name": "resume",
+        "type": "function",
+        "description": "If speech was paused, resumes speaking where it left off.",
+        "parameters": []

[not at google - send to devlin, 2013/05/20 17:29:53]

incidentally maybe all of these "parameters: []" should be removed, the schema
code can all handle it not being there so it just means we're creating a bunch
of unnecessary empty lists.

+      },
+      {
         "name": "isSpeaking",
         "type": "function",
         "description": "Checks whether the engine is currently speaking. On Mac OS X, the result is true whenever the system speech engine is speaking, even if the speech wasn't initiated by Chrome.",
         "parameters": [
           {
             "type": "function",
             "name": "callback",
             "optional": true,
             "parameters": [
               {
@@ skipping 36 matching lines @@
             "name": "event",
             "$ref": "TtsEvent",
             "description": "The event from the text-to-speech engine indicating the status of this utterance."
           }
         ],
         "description": "Used to pass events back to the function calling speak()."
       }
     ]
   }
 ]