[jdk17u-dev] RFR: 8300265: Remove metaprogramming/isSigned.hpp

[George Adams]

Prerequisite to bumping gtest, applies cleanly

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Depends on: https://git.openjdk.org/jdk17u-dev/pull/2692

Commit messages:
 - Backport 03a9a88efbb68537e24b7de28c5b81d6cd8fdb04

Changes: https://git.openjdk.org/jdk17u-dev/pull/2693/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk17u-dev&pr=2693&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8300265
  Stats: 104 lines in 6 files changed: 3 ins; 90 del; 11 mod
  Patch: https://git.openjdk.org/jdk17u-dev/pull/2693.diff
  Fetch: git fetch https://git.openjdk.org/jdk17u-dev.git pull/2693/head:pull/2693

PR: https://git.openjdk.org/jdk17u-dev/pull/2693