Bug 790570: Enabling mute will reduce the speakerphone volume on a connected. r=philikon

call. r=philikon
    1. On the function for microphoneMuted and speakerEnabled, the phone state
       should be kept on PHONE_STATE_IN_CALL.
    2. PHONE_STATE_IN_COMMUNICATION is used for audio/video chating or VOIP
       call.
    3. Change the phone state will effect the audio strategy which will tune
       volume for each audio stream type.

dom/system/gonk/RadioInterfaceLayer.js

@@ -1327,9 +1327,6 @@ RadioInterfaceLayer.prototype = {
     if (value == this.microphoneMuted) {
       return;
     }
-    gAudioManager.phoneState = value ?
-      nsIAudioManager.PHONE_STATE_IN_COMMUNICATION :
-      nsIAudioManager.PHONE_STATE_IN_CALL;  //XXX why is this needed?
     gAudioManager.microphoneMuted = value;
 
     if (!this._activeCall) {
@@ -1345,7 +1342,6 @@ RadioInterfaceLayer.prototype = {
     if (value == this.speakerEnabled) {
       return;
     }
-    gAudioManager.phoneState = nsIAudioManager.PHONE_STATE_IN_CALL; // XXX why is this needed?
     let force = value ? nsIAudioManager.FORCE_SPEAKER :
                         nsIAudioManager.FORCE_NONE;
     gAudioManager.setForceForUse(nsIAudioManager.USE_COMMUNICATION, force);