and @davidflanagan  what do you think if I put the query code to [here](https://github.com/yurenju/gaia/blob/c7423d25bc64afe2e0b4359b1cb18209429a0874/apps/camera/js/camera.js#L356-L365)? we had another mozSetting query here so looks good to put it together, like that:

from:
```javascript
    if ('mozSettings' in navigator) {
      var req = navigator.mozSettings.createLock().get(this._shutterKey);
      req.onsuccess = (function onsuccess() {
        this._shutterSoundEnabled = req.result[this._shutterKey];
      }).bind(this);

      navigator.mozSettings.addObserver(this._shutterKey, (function(e) {
        this._shutterSoundEnabled = e.settingValue;
      }).bind(this));
    }
```

to:
```javascript
    if ('mozSettings' in navigator) {
      var lock = navigator.mozSettings.createLock();

      var shutterRequest = lock.get(this._shutterKey);
      shutterRequest.onsuccess = (function onsuccess() {
        this._shutterSoundEnabled = shutterRequest.result[this._shutterKey];
      }).bind(this);

      navigator.mozSettings.addObserver(this._shutterKey, (function(e) {
        this._shutterSoundEnabled = e.settingValue;
      }).bind(this));

      var preferredSizesRequest = lock.get('camera.recording.preferredSizes');
      preferredSizesRequest.onsuccess = (function onsuccess() {
        this._preferredRecordinSizes = preferredSizesRequest
          .result['camera.recording.preferredSizes'];
      }.bind(this));
    }
```