old_contents: 
  (function() {
  
  if(typeof(L) == "undefined") 
    return;
  
  /**
   * this is a dummy layer class that modifies the leaflet DOM element background 
   * instead of creating a layer with div
   */
  var LeafLetPlainLayerView = L.Class.extend({
    includes: L.Mixin.Events,
  
    initialize: function(layerModel, leafletMap) {
      cdb.geo.LeafLetLayerView.call(this, layerModel, this, leafletMap);
    },
  
    onAdd: function() {
      this.redraw();
    },
  
    onRemove: function() { 
    },
  
    _modelUpdated: function() {
      this.redraw();
    },
  
    redraw: function() {
      var div = this.leafletMap.getContainer()
      div.style.backgroundColor = this.model.get('color');
      if(this.model.get('image')) {
        var st = 'url(' + this.model.get('image') + ') repeat center center';
        if(this.model.get('color')) {
          div.style.background = st + ' ' + this.model.get('color');
        }
      }
    }
  });
  
  _.extend(LeafLetPlainLayerView.prototype, cdb.geo.LeafLetLayerView.prototype);
  
  cdb.geo.LeafLetPlainLayerView = LeafLetPlainLayerView;
  
  })();
  
new_contents: 
  (function() {
  
  if(typeof(L) == "undefined") 
    return;
  
  /**
   * this is a dummy layer class that modifies the leaflet DOM element background 
   * instead of creating a layer with div
   */
  var LeafLetPlainLayerView = L.Class.extend({
    includes: L.Mixin.Events,
  
    initialize: function(layerModel, leafletMap) {
      cdb.geo.LeafLetLayerView.call(this, layerModel, this, leafletMap);
    },
  
    onAdd: function() {
      this.redraw();
    },
  
    onRemove: function() { 
    },
  
    _modelUpdated: function() {
      this.redraw();
    },
  
    redraw: function() {
      var div = this.leafletMap.getContainer()
      div.style.backgroundColor = this.model.get('color') || '#FFF';
      if(this.model.get('image')) {
        var st = 'url(' + this.model.get('image') + ') repeat center center';
        if(this.model.get('color')) {
          div.style.background = st + ' ' + this.model.get('color');
        }
      }
    }
  });
  
  _.extend(LeafLetPlainLayerView.prototype, cdb.geo.LeafLetLayerView.prototype);
  
  cdb.geo.LeafLetPlainLayerView = LeafLetPlainLayerView;
  
  })();
  
subject: set default color for plain layer