RFR: 8332252: Clean up vmTestbase/vm/share [v3]

[Leonid Mesnik]

> The vmTestbase/vm/share is a shared test library for vmTestbase tests. This library contains a lot of code that is used by only by small number of tests or not used at all. There are no plans to actively develop new tests in vmTestsbase and improve this shared library. 
> The final goal of this and the following PRs is to reduce the maintenance cost of vmTestbase by eliminating this library.
> 
> Also, this PR moves test-specific code into corresponding test directories to increase code locality. This allows later easier move tests from vmTestbase.
> 
> The few remaining classes include 
> InMemoryJavaCompiler.java
> that is very similar to same class from the standard testlibrary and could be merge with it and
> ProcessUtils.java
> which is used by
> test/hotspot/jtreg/runtime/Thread/TestBreakSignalThreadDump.java
> and thus should be moved into the standard testlibrary.
> The stack and options might be merged in nsk/share test library.

Leonid Mesnik has updated the pull request incrementally with one additional commit since the last revision:

  removed unused import

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

Changes:
  - all: https://git.openjdk.org/jdk/pull/19727/files
  - new: https://git.openjdk.org/jdk/pull/19727/files/f8a637dc..53757d6f

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=19727&range=02
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=19727&range=01-02

  Stats: 2 lines in 1 file changed: 0 ins; 1 del; 1 mod
  Patch: https://git.openjdk.org/jdk/pull/19727.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/19727/head:pull/19727

PR: https://git.openjdk.org/jdk/pull/19727