readRawValue() {
    if (this.type === "int") {
      return this.readInt53()
    } else if (this.type === "uint") {
      return this.readUint53()
    } else if (this.type === "utf8") {
      return this.readPrefixedString()
    } else {
      throw new RangeError(`Unknown RLEDecoder datatype: ${this.type}`)
    }
  }
Private method, do not call from outside the class.
Reads one value of the datatype configured on construction.