Add sample extensions that use the text-to-speech (TTS) API.

chrome/common/extensions/docs/examples/extensions/talking_alarm_clock/manifest.json

+{
+  "name": "Talking Alarm Clock",
+  "version": "1.3",
+  "description": "A clock with two configurable alarms that will play a sound and speak a phrase of your choice.",
+  "permissions": [ "background", "tts" ],
+
+  "background_page": "background.html",
+
+  "popup": "popup.html",
+
+  "browser_action": {
+    "default_icon": "clock-19.png",
+    "default_title": "Talking Alarm Clock",
+    "default_popup": "popup.html"
+  },
+
+  "icons": {
+    "16": "clock-16.png",
+    "48": "clock-48.png",
+    "128": "clock-128.png",
+    "256": "clock-256.png"
+  }
+}