static updateBoxSize_(dataArray, boxStart, newBoxSize) {
    const ContentWorkarounds = shaka.media.ContentWorkarounds;
    const boxView = shaka.util.BufferUtils.toDataView(dataArray, boxStart);
    const sizeField = boxView.getUint32(ContentWorkarounds.BOX_SIZE_OFFSET_);
    if (sizeField == 0) { // Means "the rest of the box".
      // No adjustment needed for this box.
    } else if (sizeField == 1) { // Means "use 64-bit size box".
      // Set the 64-bit int in two 32-bit parts.
      // The high bits should definitely be 0 in practice, but we're being
      // thorough here.
      boxView.setUint32(ContentWorkarounds.BOX_SIZE_64_OFFSET_,
          newBoxSize >> 32);
      boxView.setUint32(ContentWorkarounds.BOX_SIZE_64_OFFSET_ + 4,
          newBoxSize & 0xffffffff);
    } else { // Normal 32-bit size field.
      // Not checking the size of the value here, since a box larger than 4GB is
      // unrealistic.
      boxView.setUint32(ContentWorkarounds.BOX_SIZE_OFFSET_, newBoxSize);
    }
  }
Modify an MP4 box's size field in-place.

@param {!Uint8Array} dataArray
@param {number} boxStart The start position of the box in dataArray.
@param {number} newBoxSize The new size of the box.
@private