code: function applyThemeColors(element, colorExpression) {
        try {
          if (colorExpression) {
            // Assign the calculate RGBA color values directly as inline CSS
            element.css(interpolateColors(colorExpression));
          }
        } catch (e) {
          $log.error(e.message);
        }
      }
docs: ******************************************** Internal Methods ******************************************** 
  @ngdoc method
  @name $mdColors#applyThemeColors
  
  @description
  Lookup a set of colors by hue, theme, and palette, then apply those colors
  with the provided opacity (via `rgba()`) to the specified CSS property.
  
  @param {angular.element} element the element to apply the styles to
  @param {Object} colorExpression Keys are CSS properties and values are strings representing
  the `theme-palette-hue-opacity` of the desired color. For example:
  `{'color': 'red-A200-0.3', 'background-color': 'myTheme-primary-700-0.8'}`. Theme, hue, and
  opacity are optional.