Merge changes Ia566fce6,I36f03c07,I81492f7f

* changes:
  This is a rollforward of cl/167332236
  Updating voicemail notifications
  Updating voicemail notifications for transcription, part 2
tree: ff70d3252b4b25337cc0ad18933e8fab02adc8a0
  1. assets/
  2. java/
  3. Android.mk
  4. AndroidManifest.xml
  5. CONTRIBUTING
  6. LICENSE