code: function(data, options) {
          HeatMapTile.call(this, data, options);
  
          this._extendedWidth = options.extendedWidth;
          this._extendedHeight = options.extendedHeight;
          this._gradient = this.gradient(options.intensityGradient);
      }
docs: Constructs a HeatMapColoredTile.
  
  The default implementation using the shades of gray to draw the information produced by the HeatMapTile is a source
  for coloring. This class colours the provided canvas based on the information contained in the intensityGradient.
  
  @inheritDoc
  
  @alias HeatMapColoredTile
  @constructor
  @augments HeatMapTile
  @classdesc Tile for the HeatMap layer visualising data on a canvas using colour scale.
  @param options.intensityGradient {Object} Keys represent the opacity between 0 and 1 and the values represent
  color strings.
  @param options.extendedWidth {Number} Optional. Minimal width that needs to be retrieved for colorization.
  @param options.extendedHeight {Number} Optional. Minimal height that needs to be retrieved for colorization.