docs: function animate(timing, styles) {
  	        if (styles === void 0) { styles = null; }
  	        var stylesEntry = styles;
  	        if (!isPresent(stylesEntry)) {
  	            var EMPTY_STYLE = {};
  	            stylesEntry = new AnimationStyleMetadata([EMPTY_STYLE], 1);
  	        }
  	        return new AnimationAnimateMetadata(timing, stylesEntry);
  	    }