RFR: 8290075: [JVMCI] only blessed methods can link against EventWriterFactory.getEventWriter

[Doug Simon]

[JDK-8282420](https://bugs.openjdk.org/browse/JDK-8282420) introduced the notion of "blessed methods" which are those that can link against `jdk.jfr.internal.event.EventWriterFactory.getEventWriter(long)`.
This PR enhances the JVMCI ConstantPool API so that it can take a caller context when resolving a method to enforce this constraint properly.

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Commit messages:
 - support special linkage rules for jdk.jfr.internal.event.EventWriterFactory.getEventWriter(long) in JVMCI

Changes: https://git.openjdk.org/jdk/pull/9449/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=9449&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8290075
  Stats: 144 lines in 11 files changed: 126 ins; 6 del; 12 mod
  Patch: https://git.openjdk.org/jdk/pull/9449.diff
  Fetch: git fetch https://git.openjdk.org/jdk pull/9449/head:pull/9449

PR: https://git.openjdk.org/jdk/pull/9449