RFR: 8259845: Move placeholder implementation details to cpp file and add logging [v2]

[Coleen Phillimore]

> See CR for details.
> Tested with tier1-3 and manually by looking at the output.

Coleen Phillimore has updated the pull request incrementally with one additional commit since the last revision:

  Make 'log' inline.

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Changes:
  - all: https://git.openjdk.java.net/jdk/pull/2204/files
  - new: https://git.openjdk.java.net/jdk/pull/2204/files/75db86dd..e216f026

Webrevs:
 - full: https://webrevs.openjdk.java.net/?repo=jdk&pr=2204&range=01
 - incr: https://webrevs.openjdk.java.net/?repo=jdk&pr=2204&range=00-01

  Stats: 1 line in 1 file changed: 0 ins; 0 del; 1 mod
  Patch: https://git.openjdk.java.net/jdk/pull/2204.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/2204/head:pull/2204

PR: https://git.openjdk.java.net/jdk/pull/2204