[code-reflection] Integrated: Fix up experiment module. Also autogen config.h

[Gary Frost]

I had missed some import issues in the 'experiments' module. This PR fixes those. 

Also we now autogen config.h from java side.

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Commit messages:
 - Fix up experiment module. Also autogen config.h

Changes: https://git.openjdk.org/babylon/pull/455/files
  Webrev: https://webrevs.openjdk.org/?repo=babylon&pr=455&range=00
  Stats: 637 lines in 25 files changed: 470 ins; 110 del; 57 mod
  Patch: https://git.openjdk.org/babylon/pull/455.diff
  Fetch: git fetch https://git.openjdk.org/babylon.git pull/455/head:pull/455

PR: https://git.openjdk.org/babylon/pull/455