RFR: Prototype AOTMXBean

[Mat Carter]

/**
      * Returns the string representing the current AOT mode of
      * operation.
      *
      * @return the string representing the current AOT mode.
      */
     public String getMode();

     /**
      * Tests if a recording is in progress.
      *
      * @return {@code true} if a recording is in progress; {@code false} otherwise.
      */
     public boolean isRecording();

     /**
      * If a recording is in progress or has been completed, then returns the duration in milliseconds
      *
      * @return duration of the recording in milliseconds.
      */
     public long getRecordingDuration();

     /**
      * If a recording is in progress, then stops the recording.
      *
      * @return {@code true} if a recording was stopped; {@code false} otherwise.
      */
     public boolean endRecording();

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Commit messages:
 - Add AOTMXBean test
 - Prototype AOTMXBean

Changes: https://git.openjdk.org/leyden/pull/52/files
  Webrev: https://webrevs.openjdk.org/?repo=leyden&pr=52&range=00
  Stats: 499 lines in 13 files changed: 497 ins; 0 del; 2 mod
  Patch: https://git.openjdk.org/leyden/pull/52.diff
  Fetch: git fetch https://git.openjdk.org/leyden.git pull/52/head:pull/52

PR: https://git.openjdk.org/leyden/pull/52