function onChangeScrollShrink(shrinkWithScroll) {
          var closestContent = $mdUtil.getSiblings(element, 'md-content');

          // If there are content elements, fake the call using the first content element.
          // This might still fail if the content element isn't a sibling of the toolbar.
          if (!contentElement && closestContent.length) {
            onMdContentLoad(null, closestContent[0]);
          }

          // Evaluate the expression
          shrinkWithScroll = scope.$eval(shrinkWithScroll);

          // Disable only if the attribute's expression evaluates to false
          if (shrinkWithScroll === false) {
            disableScrollShrink();
          } else {
            disableScrollShrink = enableScrollShrink();
          }
        }
@param {string} shrinkWithScroll value of md-scroll-shrink attribute