Disclose browser speech processing before microphone use

voice.js

@@ -201,7 +201,8 @@
     function getState() { return state; }
     function getSettings() { return {...settings}; }
     function getVoices() { return availableVoices(); }
-    return {startListening, stopListening, speak, cancelSpeech, stopAll, update, getState, getSettings, getVoices};
+    function supportsRecognition() { return Boolean(win.SpeechRecognition || win.webkitSpeechRecognition); }
+    return {startListening, stopListening, speak, cancelSpeech, stopAll, update, getState, getSettings, getVoices, supportsRecognition};
   }
 
   root.GameVoice = {createVoiceController, DEFAULT_SETTINGS, parseVoiceCommand, loadSettings, saveSettings};