RFR: 8158801: [TEST_BUG] Mixing tests fail because of focus workaround trick [v5]

[Khalid Boulanouare]

> Many Mixing tests failed because the work around click lands on the minimizing area in the window control and causes the tests to fail.
> 
> This fix changes the width of base frames which allows most of tests to pass.

Khalid Boulanouare 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 seven additional commits since the last revision:

 - Merge branch 'openjdk:master' into jdk-8158801
 - Merge branch 'openjdk:master' into jdk-8158801
 - Merge branch 'openjdk:master' into jdk-8158801
 - Changes protected fields to static
 - Problem list files for Mac OS only
 - Removes passed tests from problem list
 - Changes Frame width to 300, uses protected constants for all base tests frame sizes

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

Changes:
  - all: https://git.openjdk.org/jdk/pull/25971/files
  - new: https://git.openjdk.org/jdk/pull/25971/files/6fe853a8..3b0c2462

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=25971&range=04
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=25971&range=03-04

  Stats: 28415 lines in 852 files changed: 17113 ins; 5986 del; 5316 mod
  Patch: https://git.openjdk.org/jdk/pull/25971.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/25971/head:pull/25971

PR: https://git.openjdk.org/jdk/pull/25971