addVisibilityBlock method

void addVisibilityBlock ()

Implementation

void addVisibilityBlock() {
  visibilityBlocks ??= 0;
  visibilityBlocks++;

//2.5.3 20151120
// Node.prototype.addVisibilityBlock = function () {
//     if (this.visibilityBlocks == null) {
//         this.visibilityBlocks = 0;
//     }
//     this.visibilityBlocks = this.visibilityBlocks + 1;
// };
}