code: function setMeta(name, content) {
        mapExistingElement(name);
  
        if (!metaElements[name]) {
          var newMeta = angular.element('<meta name="' + name + '" content="' + content + '"/>');
          head.append(newMeta);
          metaElements[name] = newMeta;
        }
        else {
          metaElements[name].attr('content', content);
        }
  
        return function () {
          metaElements[name].attr('content', '');
          metaElements[name].remove();
          delete metaElements[name];
        };
      }
docs: @ngdoc method
  @name $$mdMeta#setMeta
  
  @description
  Creates meta element with the 'name' and 'content' attributes,
  if the meta tag is already created than we replace the 'content' value
  
  @param {string} name meta tag 'name' attribute value
  @param {string} content meta tag 'content' attribute value
  @returns {function} remove function