[foreign-preview] RFR: Tweak warning text for restricted method access

[Maurizio Cimadamore]

Following some internal feedback, the new warning for restricted method access has been tweaked to this:


WARNING: A restricted method in <class> has been called
WARNING: <method> has been called by <module>
WARNING: Use --enable-native-access=<module> to avoid a warning for this module


For instance:


WARNING: A restricted method in java.lang.foreign.CLinker has been called
WARNING: java.lang.foreign.CLinker::systemCLinker has been called by module panama_module
WARNING: Use --enable-native-access=panama_module to avoid a warning for this module


or, for unnamed modules:


WARNING: A restricted method in java.lang.foreign.CLinker has been called
WARNING: java.lang.foreign.CLinker::systemCLinker has been called by the unnamed module
WARNING: Use --enable-native-access=ALL-UNNAMED to avoid a warning for this module


This new text helps better connecting the waring with the action that a developer might want to take to get rid of the warning.

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Commit messages:
 - Tweak warning text

Changes: https://git.openjdk.java.net/panama-foreign/pull/660/files
 Webrev: https://webrevs.openjdk.java.net/?repo=panama-foreign&pr=660&range=00
  Stats: 10 lines in 2 files changed: 1 ins; 0 del; 9 mod
  Patch: https://git.openjdk.java.net/panama-foreign/pull/660.diff
  Fetch: git fetch https://git.openjdk.java.net/panama-foreign pull/660/head:pull/660

PR: https://git.openjdk.java.net/panama-foreign/pull/660