RFR: 8360498: [TEST_BUG] Some Mixing test continue to fail [v14]

[Khalid Boulanouare]

> This PR will consolidate fixes of the following bugs:
> 
> https://bugs.openjdk.org/browse/JDK-8361188
> https://bugs.openjdk.org/browse/JDK-8361189
> https://bugs.openjdk.org/browse/JDK-8361190
> https://bugs.openjdk.org/browse/JDK-8361191
> https://bugs.openjdk.org/browse/JDK-8361192
> https://bugs.openjdk.org/browse/JDK-8361193
> https://bugs.openjdk.org/browse/JDK-8361195
> 
> This PR depends on https://github.com/openjdk/jdk/pull/25971
> 
> For test : java/awt/Mixing/AWT_Mixing/JComboBoxOverlapping.java, the fix suggested is to return false in method isValidForPixelCheck for embedded frame, in which case the component is set to null. For more details see bug: [JDK-8361188](https://bugs.openjdk.org/browse/JDK-8361188)
> 
> For test : test/jdk/java/awt/Mixing/AWT_Mixing/MixingPanelsResizing.java, I had to create a a tolerance color matching method for mac for the tests to pass. Also, the jbuttons needed to have different color than the color of the background frame, in order for test to pass. For more detail see bug: https://bugs.openjdk.org/browse/JDK-8361193
> 
> For test : test/jdk/java/awt/Mixing/AWT_Mixing/JSplitPaneOverlapping.java, it seems that color selected for lightweight component matches the background color of the frame. And this will cause the test to fail when matching colors. Choosing any color different than the background color will get the test to pass. For more details, see bug: https://bugs.openjdk.org/browse/JDK-8361192
> 
> For test test/jdk/java/awt/Mixing/AWT_Mixing/JPopupMenuOverlapping.java, it looks like the frame when visible, the popup test does not work properly. The frame needs to be hidden for the test to click on popup. For more details see bug: https://bugs.openjdk.org/browse/JDK-8361191
> 
> For test test/jdk/java/awt/Mixing/AWT_Mixing/JMenuBarOverlapping.java, the test runs successfully but it times out after the default 2 minutes of jtreg. increasing the timeout to 3 minutes get the test to pass. For more details please refer to bug: https://bugs.openjdk.org/browse/JDK-8361190

Khalid Boulanouare has updated the pull request incrementally with four additional commits since the last revision:

 - Removes not needed changes
 - Revert "Removes not needed changes"
   
   This reverts commit e76780d50cc390e35443dccb193cfbc9a1cec1cb.
 - Removes not needed changes
 - Removes extra white lines

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

Changes:
  - all: https://git.openjdk.org/jdk/pull/26625/files
  - new: https://git.openjdk.org/jdk/pull/26625/files/b2a35b87..2888ff38

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=26625&range=13
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=26625&range=12-13

  Stats: 2 lines in 1 file changed: 0 ins; 2 del; 0 mod
  Patch: https://git.openjdk.org/jdk/pull/26625.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/26625/head:pull/26625

PR: https://git.openjdk.org/jdk/pull/26625