RFR: 8338930: StringConcatFactory static string concatenation strategy

[Shaojin Wen]

This is a follow-up to PR #20273, which improves performance when the number of parameters exceeds 20.

When the number of parameters is large, the possibility of reuse will be lower, so we can use the static concat method and write the length and coder directly into the bytecode to solve the performance regression problem.

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Commit messages:
 - Optimize the construction of MethodType and MethodTypeDesc to reduce memory allocation
 - revert code style
 - from suggest
 - Update src/java.base/share/classes/java/lang/invoke/StringConcatFactory.java
 - support staticConcat

Changes: https://git.openjdk.org/jdk/pull/20675/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=20675&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8338930
  Stats: 159 lines in 3 files changed: 90 ins; 11 del; 58 mod
  Patch: https://git.openjdk.org/jdk/pull/20675.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/20675/head:pull/20675

PR: https://git.openjdk.org/jdk/pull/20675