Add initial support for Bluetooth voice dialing.
Bug: 2432200
This adds a new BluetoothVoiceDialerActivity,
because the flow for bluetooth is so different from the regular VoiceDialerActivity.
This involved breaking RecognizerEngine's direct dependence on VoiceDialerActivity to
make callbacks on. RecognizerEngine now makes callbacks on an interface called RecognizerClient,
which is implemented by several different helper classes for different reasons.
I've made RecognizerEngine an abstract base class, it handles some general setup, logging, etc.
but it is up to the subclasses to set up the grammar and handle the results when recognition
succeeds. There are currently two subclasses, the CommandRecognizerEngine recognizes
phrases to call people, dial numbers, and open applications. The YesNoRecognizerEngine recognizes
"yes" and "no".
Known issues as of this checkin:
* 8khz audio has not been validated, it's not certain that the Recognizer is getting a good audio stream.
* There is still a problem with audio routing, the TTS output switches randomly between the speaker and
the headset.
* only the simplest case is supported, there's not a clean solution when there are multiple
possible matches.
* there are cases where the activity really should wait for the TTS utterance to finish before
moving on.
* we don't have a solution for when the phone is locked and the user activates bluetooth voicedial.
* the flow may or may not be ideal, the "no matches, try again" option may not be useful. We will
let some people try this and then revisit the approach.
9 files changed
