[lworld+vector] RFR: Merge lworld

[Xiaohong Gong]

This patch merges the latest `valhalla:lworld` to
 `valhalla:lworld+vector` branch, together with following
 main changes:

1. Resolve conflicts mainly caused by the BACKOUT of
 `VectorShuffle refactory` in jdk mainline [1].
2. Fix the class id issue for `SafePointScalarMergeNode` added by [JDK-8287061](https://bugs.openjdk.java.net/browse/JDK-8287061). This causes an jvm crash
 when building the jdk image. `lworld` branch also
 fixes it (see [2]), but it seems the id is not correctly
 ordered.

[1] https://github.com/openjdk/jdk/pull/14629

[2] https://github.com/openjdk/valhalla/blob/lworld/src/hotspot/share/opto/node.hpp#L738

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

Commit messages:
 - [lworld+vector] Merge lworld
 - 8314923: [lworld] AllocationMergesTests.java fails IR verification
 - Merge jdk
 - 8313081: MonitoringSupport_lock should be unconditionally initialized after 8304074
 - 8309088: security/infra/java/security/cert/CertPathValidator/certification/AmazonCA.java fails
 - 8313087: DerValue::toString should output a hex view of the values in byte array
 - 4800398: (ch spec) Clarify Channels.newChannel(InputStream) spec
 - 8313155: Problem list some JUnit-based tests in test/jdk/java/lang/invoke
 - 8312445: Array types in annotation elements show square brackets twice
 - 8312526: Test dk/jfr/event/oldobject/TestHeapDeep.java failed: Could not find ChainNode
 - ... and 819 more: https://git.openjdk.org/valhalla/compare/c073a2fd...9890580d

The webrevs contain the adjustments done while merging with regards to each parent branch:
 - lworld+vector: https://webrevs.openjdk.org/?repo=valhalla&pr=921&range=00.0
 - lworld: https://webrevs.openjdk.org/?repo=valhalla&pr=921&range=00.1

Changes: https://git.openjdk.org/valhalla/pull/921/files
  Stats: 238118 lines in 3830 files changed: 127006 ins; 91855 del; 19257 mod
  Patch: https://git.openjdk.org/valhalla/pull/921.diff
  Fetch: git fetch https://git.openjdk.org/valhalla.git pull/921/head:pull/921

PR: https://git.openjdk.org/valhalla/pull/921