RFR: 8150564: Migrate useful ExtendedRobot methods into awt.Robot [v3]

[Alisen Chung]

> Some useful methods in ExtendedRobot should be migrated into Robot itself so that ExtendedRobot can be removed in the future. The tests using ExtendedRobot for these migrated methods are changed to use only Robot (removing unnecessary building of ExtendedRobot).

Alisen Chung has updated the pull request with a new target base due to a merge or a rebase. The pull request now contains nine commits:

 - Merge branch 'master' of https://github.com/openjdk/jdk into 8150564
 - merge
 - move mouseMove back to ER
 - extendedRobot
 - Merge branch 'master' of https://github.com/openjdk/jdk into 8150564
 - fix spacing
 - fix tests
 - added tests
 - init commit

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Changes: https://git.openjdk.org/jdk/pull/22044/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=22044&range=02
  Stats: 852 lines in 236 files changed: 249 ins; 430 del; 173 mod
  Patch: https://git.openjdk.org/jdk/pull/22044.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/22044/head:pull/22044

PR: https://git.openjdk.org/jdk/pull/22044