RFR: 8291991: Adjust the "shared class paths mismatch" message if class path logging is enabled [v4]

[Calvin Cheung]

> Before this fix, with `-Xshare:on` and `-Xlog:class+path=info` and if there is a class path mismatch, the following error message will be displayed:
> 
> `shared class paths mismatch (hint: enable -Xlog:class+path=info to diagnose the failure)`
> 
> After this fix, only the first part of the error message will be displayed since the "hint" is repetitive if the user has specified `-Xlog:class+path=info.`
> 
> `shared class paths mismatch`
> 
> Passed tiers 1 and 2 testing.

Calvin Cheung has updated the pull request incrementally with one additional commit since the last revision:

  simplify FileMapInfo::fail_continue_impl

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

Changes:
  - all: https://git.openjdk.org/jdk/pull/11078/files
  - new: https://git.openjdk.org/jdk/pull/11078/files/4b3d7fd6..ed95ee8c

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=11078&range=03
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=11078&range=02-03

  Stats: 6 lines in 1 file changed: 0 ins; 3 del; 3 mod
  Patch: https://git.openjdk.org/jdk/pull/11078.diff
  Fetch: git fetch https://git.openjdk.org/jdk pull/11078/head:pull/11078

PR: https://git.openjdk.org/jdk/pull/11078