RFR: 8290005: com/sun/jndi/ldap/LdapCBPropertiesTest.java failling with NullPointerException [v2]

[Matthew Donovan]

> In this PR, I added methods to the TransportContext class to synchronize access to the handshakeContext field. I also updated locations in the code that rely on the handshakeContext field to not be null to use the synchronized methods.
> 
> Thanks

Matthew Donovan has updated the pull request incrementally with one additional commit since the last revision:

  using try/finally in terminateHandshakeContext and using local context variable in all places it should be

-------------

Changes:
  - all: https://git.openjdk.org/jdk/pull/13742/files
  - new: https://git.openjdk.org/jdk/pull/13742/files/fe2604aa..ce88caa0

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=13742&range=01
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=13742&range=00-01

  Stats: 7 lines in 2 files changed: 3 ins; 0 del; 4 mod
  Patch: https://git.openjdk.org/jdk/pull/13742.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/13742/head:pull/13742

PR: https://git.openjdk.org/jdk/pull/13742