[jdk20] RFR: 8300269: The selected item in an editable JComboBox with titled border is not visible in Aqua LAF [v2]

[Damon Nguyen]

> Fixes regression bug where Aqua L&F editable JComboBox with a TitledBorder was not visible. 
> 
> This fix adds a conditional that addresses cases where a border is used on an AquaComboBox. The patch that caused the issue set a static height, but this height caused issues with a TitledBorder, which modifies the height to account for the border. In this case, revert to the old method of calculating a comboBox's height.
> 
> A point made in the previous PR was that the previous method had +1 to comboBox height. This could be re-added, but in the comment thread in [the previous PR](https://github.com/openjdk/jdk/pull/12087), leaving this out is better because the extra height causes the textField to be skewed South.
> 
> <img width="63" alt="Screen Shot 2023-01-20 at 12 54 47 PM" src="https://user-images.githubusercontent.com/96267980/214998560-2340ac1d-5df3-47ba-94f7-56459211330e.png">
> 
> This also adds the test that checks an editable JComboBox across all L&F's except GTK. There seems to be an unrelated bug to this fix that causes GTK L&F comboBoxes to not behave as expected with these key presses.

Damon Nguyen has updated the pull request incrementally with one additional commit since the last revision:

  Change return to continue

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Changes:
  - all: https://git.openjdk.org/jdk20/pull/119/files
  - new: https://git.openjdk.org/jdk20/pull/119/files/1cb97b3f..05e8342b

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk20&pr=119&range=01
 - incr: https://webrevs.openjdk.org/?repo=jdk20&pr=119&range=00-01

  Stats: 1 line in 1 file changed: 0 ins; 0 del; 1 mod
  Patch: https://git.openjdk.org/jdk20/pull/119.diff
  Fetch: git fetch https://git.openjdk.org/jdk20 pull/119/head:pull/119

PR: https://git.openjdk.org/jdk20/pull/119