RFR: Merge jdk

[Mikael Vidstedt]

Merge in jdk-15+36

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

Commit messages:
 - Merge jdk
 - 8246031: SSLSocket.getSession() doesn't close connection for timeout/ interrupts
 - 8251276: JDK-8248299 breaks JDK 15 validate-headers build
 - 8248299: two jdeps files miss copyright header
 - Added tag jdk-15+35 for changeset fd60c3146a02
 - 8249628: Remove EA from JDK 15 version string starting with Initial RC promotion
 - 8250609: C2 crash in IfNode::fold_compares
 - 8248597: [Graal] api/java_security/SignatureSpi/DelegationTests.html fails with Method "javasoft.sqe.tests.api.java.security.SignatureSpi.JCKSignatureSpi.clear" doesn't exist
 - 8250770: Net.java translateToSocketException does not handle IOException
 - Added tag jdk-15+34 for changeset b0817631d2f4
 - ... and 91 more: https://git.openjdk.java.net/portola/compare/0b2dbf5c...bc96df28

The webrevs contain the adjustments done while merging with regards to each parent branch:
 - jdk15: https://webrevs.openjdk.java.net/portola/10/webrev.00.0
 - jdk: https://webrevs.openjdk.java.net/portola/10/webrev.00.1

Changes: https://git.openjdk.java.net/portola/pull/10/files
  Stats: 10268 lines in 2887 files changed: 3563 ins; 3483 del; 3222 mod
  Patch: https://git.openjdk.java.net/portola/pull/10.diff
  Fetch: git fetch https://git.openjdk.java.net/portola pull/10/head:pull/10

PR: https://git.openjdk.java.net/portola/pull/10