function getMeta(name) {
      if (!mapExistingElement(name)) {
        throw Error('$$mdMeta: could not find a meta tag with the name \'' + name + '\'');
      }

      return metaElements[name].attr('content');
    }
@ngdoc method
@name $$mdMeta#getMeta

@description
Gets the 'content' attribute value of the wanted meta element

@param {string} name meta tag 'name' attribute value
@returns {string} content attribute value