code: function capturePointer( tracker, pointerType, pointerCount ) {
          var pointsList = tracker.getActivePointersListByType( pointerType ),
              eventParams;
  
          pointsList.captureCount += (pointerCount || 1);
  
          if ( pointsList.captureCount === 1 ) {
              if ( $.Browser.vendor === $.BROWSERS.IE && $.Browser.version < 9 ) {
                  tracker.element.setCapture( true );
              } else {
                  eventParams = getCaptureEventParams( tracker, $.MouseTracker.havePointerEvents ? 'pointerevent' : pointerType );
                  // We emulate mouse capture by hanging listeners on the document object.
                  //    (Note we listen on the capture phase so the captured handlers will get called first)
                  // eslint-disable-next-line no-use-before-define
                  if (isInIframe && canAccessEvents(window.top)) {
                      $.addEvent(
                          window.top,
                          eventParams.upName,
                          eventParams.upHandler,
                          true
                      );
                  }
                  $.addEvent(
                      $.MouseTracker.captureElement,
                      eventParams.upName,
                      eventParams.upHandler,
                      true
                  );
                  $.addEvent(
                      $.MouseTracker.captureElement,
                      eventParams.moveName,
                      eventParams.moveHandler,
                      true
                  );
              }
          }
      }
docs: Begin capturing pointer events to the tracked element.
  @private
  @inner