RFR: 8336274: MutableBigInteger.leftShift(int) optimization [v5]

[fabioromano1]

> This implementation of MutableBigInteger.leftShift(int) optimizes the current version, avoiding unnecessary copy of the MutableBigInteger's value content and performing the primitive shifting only in the original portion of the value array rather than in the value yet extended with trailing zeros.

fabioromano1 has updated the pull request with a new target base due to a merge or a rebase. The incremental webrev excludes the unrelated changes brought in by the merge/rebase. The pull request contains six additional commits since the last revision:

 - Merge branch 'openjdk:master' into patchLeftShift
 - Code more clear
 - Tests changes
 - Merge branch 'openjdk:master' into patchLeftShift
 - Removed trailing whitespace
 - MutableBigInteger.leftShift(int) optimization

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

Changes:
  - all: https://git.openjdk.org/jdk/pull/20008/files
  - new: https://git.openjdk.org/jdk/pull/20008/files/9231c600..87474ee9

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=20008&range=04
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=20008&range=03-04

  Stats: 35079 lines in 1101 files changed: 20749 ins; 9055 del; 5275 mod
  Patch: https://git.openjdk.org/jdk/pull/20008.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/20008/head:pull/20008

PR: https://git.openjdk.org/jdk/pull/20008