Console pane default levels button a11y bug fix
Console pane default levels button a11y bug fix

The "default levels" button in enabled status in high contrast dark mode:  https://imgur.com/a/rIIwkj2

The "default levels" button in disabled status in high contrast dark mode:
before https://imgur.com/a/EUEXvcP
after https://imgur.com/a/AqTQ6y8

The "default levels" button in disabled status in high contrast light mode:
before https://imgur.com/a/VGti3XN
after https://imgur.com/a/T7Lwa2N

Bug: 1255266
Change-Id: Icbb15275da4c7ce48dd6d1e2c8a634ae146b519c
Reviewed-on: https://chromium-review.googlesource.com/c/devtools/devtools-frontend/+/3198498
Commit-Queue: Guangyue Xu <8889aaaba556d6c04b6ed048317b61b150e3f6e5@microsoft.com>
Reviewed-by: Michael Liao <00d75d81082fdf74688ec453c516b42f7cbf0f40@microsoft.com>
Reviewed-by: Alex Rudenko <d8d88e7d7e77f69e23d1d1432231196fb8e02a62@chromium.org>

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