RFR: 8368185: Test javax/swing/plaf/synth/SynthButtonUI/6276188/bug6276188.java failed: Synth ButtonUI does not handle PRESSED & MOUSE_OVER state [v2]

[Prasanta Sadhukhan]

> Test frame is changed to Red for Mouse PRESSED and MOUSE_OVER state but it seem time is too less before it is moved to Green when mouse press is released so it retrieves Green instead of Red.
> Also, the pixel color retrieval point is conflicting with mouse cursor position, which gets picked up during `robot.createSceenCapture` execution so retrieval point is moved slightly up instead of down.
> 
> 100 iterations of the test passed in all platforms.

Prasanta Sadhukhan has updated the pull request incrementally with one additional commit since the last revision:

  Use latch sync

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

Changes:
  - all: https://git.openjdk.org/jdk/pull/27444/files
  - new: https://git.openjdk.org/jdk/pull/27444/files/047054c2..b8ed9879

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=27444&range=01
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=27444&range=00-01

  Stats: 16 lines in 1 file changed: 12 ins; 1 del; 3 mod
  Patch: https://git.openjdk.org/jdk/pull/27444.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/27444/head:pull/27444

PR: https://git.openjdk.org/jdk/pull/27444