RFR: Merge jdk:master

[Kevin Rushforth]

This is a merge-style PR for the initial changes needed to merge jdk/master into lanai/master so we can change the
auto-sync to use jdk/master instead of the retired client/master.

There were several merge conflicts that arose from this due to the fact that the client and jdk git repos had diverged.
This was caused by a change in the OpenJDK Census data that in turn caused a different git commit hash when converting
an identical HG commit in the client repo and the jdk repo at two different times. As a result, there are a total of
474 commits in the jdk repo that duplicate (but with a different commit hash) commits in the client repo.

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Commit messages:
 - Merge jdk:master
 - 8250217: com.sun.tools.javac.api.JavacTaskImpl swallows compiler exceptions potentially producing false positive test results
 - 8252957: Wrong comment in CgroupV1Subsystem::cpu_quota
 - 8248532: Every time I change keyboard language at my MacBook, Java crashes
 - 8252794: Creation of JNIMethodBlock should be done with a leaf lock
 - 8235229: Compilation against a modular, multi-release JAR erroneous with --release
 - 8240751: Shenandoah: fold ShenandoahTracer definition
 - 8250840: some tests use --enable-preview unnecessarily
 - 8252916: Newline in object field values list of ScopeDesc should be removed
 - 8157729: examples in LinkedHashMap and LinkedHashSet class doc use raw types
 - ... and 551 more: https://git.openjdk.java.net/lanai/compare/bcb31edf...4755e807

The webrevs contain the adjustments done while merging with regards to each parent branch:
 - master: https://webrevs.openjdk.java.net/?repo=lanai&pr=93&range=00.0
 - jdk:master: https://webrevs.openjdk.java.net/?repo=lanai&pr=93&range=00.1

Changes: https://git.openjdk.java.net/lanai/pull/93/files
  Stats: 11434 lines in 448 files changed: 8316 ins; 1527 del; 1591 mod
  Patch: https://git.openjdk.java.net/lanai/pull/93.diff
  Fetch: git fetch https://git.openjdk.java.net/lanai pull/93/head:pull/93

PR: https://git.openjdk.java.net/lanai/pull/93