Completely hide tab close button when dirty state is highlighted in top border

[usernamehw]

Fixes #64684

Before	After

[bpasero]

I am not sure this requires another setting, can we be sure people want this?

[usernamehw]

We can merge and wait for complaints.

[usernamehw]

It's not like people would actually upvote the issue #64684.

[bpasero]

I would prefer the CSS to be just more explicit via a :not() pseudo:

.monaco-workbench > .part.editor > .content .editor-group-container > .title .tabs-container > .tab.close-button-off.dirty:not(.dirty-border-top) {
	background-repeat: no-repeat;
	background-position-y: center;
	background-position-x: calc(100% - 6px); /* to the right of the tab label */
	padding-right: 28px; /* make room for dirty indication when we are running without close button */
}

.vs .monaco-workbench > .part.editor > .content .editor-group-container > .title .tabs-container > .tab.close-button-off.dirty:not(.dirty-border-top) {
	background-image: url('close-dirty.svg');
}

.vs-dark .monaco-workbench > .part.editor > .content .editor-group-container > .title .tabs-container > .tab.close-button-off.dirty:not(.dirty-border-top),
.hc-black .monaco-workbench > .part.editor > .content .editor-group-container > .title .tabs-container > .tab.close-button-off.dirty:not(.dirty-border-top) {
	background-image: url('close-dirty-inverse.svg');
}

This avoids having to repeat CSS rules that have been defined elsewhere already.

[usernamehw]

No selector for .hc because there's no modified border there.

[bpasero]

Thanks 👍