return CompactHashSet.create();
  }

  /**
   * Returns a new array of the given length with the same type as a reference array.
   *
   * @param reference any array of the desired type
   * @param length the length of the new array
   */
  /*
   * The new array contains nulls, even if the old array did not. If we wanted to be accurate, we

 *
 * @author Jesse Wilson
 */
@GwtCompatible(emulated = true)
@ElementTypesAreNonnullByDefault
final class Platform {
  private Platform() {}

  /** Returns a thread-local 1024-char array. */
  static char[] charBufferFromThreadLocal() {
    // requireNonNull accommodates Android's @RecentlyNullable annotation on ThreadLocal.get
    return requireNonNull(DEST_TL.get());
  }

  /**

    T[] result = newArray(arrayOfType, to - from);
    System.arraycopy(source, from, result, 0, to - from);
    return result;
  }

  // TODO(user): Move this logic to a utility class.
  @JsType(isNative = true, name = "Array", namespace = JsPackage.GLOBAL)
  private interface NativeArray {
    @JsProperty
    void setLength(int length);
  }

  static MapMaker tryWeakKeys(MapMaker mapMaker) {
    return mapMaker;
  }