Rename built-in speech synthesis voice names.

chrome/browser/resources/chromeos/speech_synthesis/manifest_guest.json

 {
   // NOTE: Keep two json files in this directory in sync. The only difference
   // should be incognito:split in Guest mode version.
   "name": "Chrome OS built-in text-to-speech extension",
   "version": "2.1.1",
   "description": "This is a high-quality text-to-speech (TTS) voice extension that runs in your browser using Native Client technology.",
   "manifest_version": 2,
   "incognito": "split",
   "background": {
     "scripts": [
@@ skipping 12 matching lines @@
     ]
   },
   "permissions": [
     "ttsEngine",
     "unlimitedStorage"
   ],
   "key": "MIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQDlKEJseIIbKFyX0BCWNYOWlPEUt1IxBvIoW1PI7DTmipbwyVr3s2EprewYdtr9hCO5Yzs5w/ai1Xnhet5PLAsMje6ZP0Kvq0tlVfaYF8oQHBPF+ifx31RBT7Cn+ZVKLq1fxrwzY063GVhW+CAr06Ar8YRFXtFoC4FHlUNDIoSb4wIDAQAB",
   "tts_engine": {
     "voices": [
       {
-        "voice_name": "German Female TTS (by Google)",
+        "voice_name": "Chrome OS German",
         "lang": "de-DE",
         "gender": "female",
         "event_types": [ "start", "word", "end", "error" ]
       },
       {
-        "voice_name": "GB English Female TTS (by Google)",
+        "voice_name": "Chrome OS British English",
         "lang": "en-GB",
         "gender": "female",
         "event_types": [ "start", "word", "end", "error" ]
       },
       {
-        "voice_name": "Indian English Female TTS (by Google)",
+        "voice_name": "Chrome OS Indian English",
         "lang": "en-IN",
         "gender": "female",
         "event_types": [ "start", "word", "end", "error" ]
       },
       {
-        "voice_name": "US English Female TTS (by Google)",
+        "voice_name": "Chrome OS US English",
         "lang": "en-US",
         "gender": "female",
         "event_types": [ "start", "word", "end", "error" ]
       },
       {
-        "voice_name": "Spanish Female TTS (by Google)",
+        "voice_name": "Chrome OS Spanish",
         "lang": "es-ES",
         "gender": "female",
         "event_types": [ "start", "word", "end", "error" ]
       },
       {
-        "voice_name": "US Spanish Female TTS (by Google)",
+        "voice_name": "Chrome OS US Spanish",
         "lang": "es-US",
         "gender": "female",
         "event_types": [ "start", "word", "end", "error" ]
       },
       {
-        "voice_name": "French Female TTS (by Google)",
+        "voice_name": "Chrome OS French",
         "lang": "fr-FR",
         "gender": "female",
         "event_types": [ "start", "word", "end", "error" ]
       },
       {
-        "voice_name": "Italian Female TTS (by Google)",
+        "voice_name": "Chrome OS Italian",
         "lang": "it-IT",
         "gender": "female",
         "event_types": [ "start", "word", "end", "error" ]
       },
       {
-        "voice_name": "Korean Female TTS (by Google)",
+        "voice_name": "Chrome OS Korean",
         "lang": "ko-KR",
         "gender": "female",
         "event_types": [ "start", "word", "end", "error" ]
       },
       {
-        "voice_name": "Brazilian Portuguese Female TTS (by Google)",
+        "voice_name": "Chrome OS Brazilian Portuguese",
         "lang": "pt-BR",
         "gender": "female",
         "event_types": [ "start", "word", "end", "error" ]
       }
     ]
-  },
-  "icons": {
-    "128": "google-tts-128.png",
-    "16": "google-tts-16.png",
-    "256": "google-tts-256.png",
-    "48": "google-tts-48.png"
   }
 }