Import HashSet from jdk-11.0.13-ga

List of files:
  ojluni/src/main/java/java/util/HashSet.java
  ojluni/src/test/java/util/HashSet/Serialization.java

Generated by tools/expected_upstream/ojluni_merge_to_master.py

Bug: 249243589
Test: N/A
Change-Id: I783148a498bfc313ce4e6d5dd0a85b7920a735cf
3 files changed
tree: c8f8e4bca51017831327d17301e607c12ac12795
  1. ojluni/
  2. tools/
  3. EXPECTED_UPSTREAM