);
            blockToDrag.onMouseMove_(mouseMoveEvent);

            // Drop at dx, dy.
            setTimeout(
              function() {
                var mouseUpEvent = new MouseEvent('mouseup',
                    {clientX: blockLeft + dx,
                    clientY: blockTop + dy});
                blockToDrag.onMouseUp_(mouseUpEvent);

                setTimeout(fakeDragWrapper(), 100);
              }, 30);
          }, 30);
      };

      function fakeDragWrapper() {
        var dragInfo = fake