RFR: 8254: Allow primitive types in converters [v2]

[Ralf Schmelter]

> This allows primitive types in converters.

Ralf Schmelter has updated the pull request incrementally with one additional commit since the last revision:

  Incorporated feedback

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Changes:
  - all: https://git.openjdk.org/jmc/pull/584/files
  - new: https://git.openjdk.org/jmc/pull/584/files/1e65bef6..76c91791

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jmc&pr=584&range=01
 - incr: https://webrevs.openjdk.org/?repo=jmc&pr=584&range=00-01

  Stats: 18 lines in 2 files changed: 0 ins; 0 del; 18 mod
  Patch: https://git.openjdk.org/jmc/pull/584.diff
  Fetch: git fetch https://git.openjdk.org/jmc.git pull/584/head:pull/584

PR: https://git.openjdk.org/jmc/pull/584