[lworld] RFR: Merge jdk

[David Simms]

Merge tag 'jdk-16+20'

# Conflicts:
#	src/hotspot/cpu/x86/frame_x86.cpp
#	src/hotspot/share/classfile/classFileParser.cpp
#	src/hotspot/share/opto/cfgnode.hpp
#	src/hotspot/share/runtime/thread.cpp

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

Commit messages:
 - Merge tag 'jdk-16+20' into lworld_merge_jdk_16_20
 - 8249623: test @ignore-d due to 7013634 should be returned back to execution
 - 8254345: com/sun/jdi/JdwpAttachTest.java reports error incorrectly
 - 8254012: NMT: MetaspaceSnapshot::snapshot uses wrong enum
 - 8254775: Microbenchmark StringIndexOfChar doesn't compile
 - 8254761: Wrong intrinsic annotation used for StringLatin1.indexOfChar
 - 8254744: Clean-up CodeBlob::align_code_offset
 - 8173585: Intrinsify StringLatin1.indexOf(char)
 - 8254586: Replace fthrow() calls with simpler method calls in classFileParser.cpp
 - 8254748: Bad Copyright header format after JDK-8212218
 - ... and 102 more: https://git.openjdk.java.net/valhalla/compare/85f6d5b6...99696d60

The webrevs contain the adjustments done while merging with regards to each parent branch:
 - lworld: https://webrevs.openjdk.java.net/?repo=valhalla&pr=227&range=00.0
 - jdk: https://webrevs.openjdk.java.net/?repo=valhalla&pr=227&range=00.1

Changes: https://git.openjdk.java.net/valhalla/pull/227/files
  Stats: 22363 lines in 573 files changed: 13396 ins; 5024 del; 3943 mod
  Patch: https://git.openjdk.java.net/valhalla/pull/227.diff
  Fetch: git fetch https://git.openjdk.java.net/valhalla pull/227/head:pull/227

PR: https://git.openjdk.java.net/valhalla/pull/227