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

[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.

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Commit messages:
 - Change line separator
 - Fix carriage return
 - Fix height issue with border. Add test

Changes: https://git.openjdk.org/jdk20/pull/119/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk20&pr=119&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8300269
  Stats: 184 lines in 2 files changed: 183 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