src/vs/workbench/contrib/mergeEditor/browser/view/editors/inputCodeEditorView.ts/MergeConflictGutterItemView/layout
class MergeConflictGutterItemView:	layout(top: number, height: number, viewTop: number, viewHeight: number): void {
		this.target.classList.remove('multi-line');
		this.target.classList.remove('single-line');
		this.target.classList.add(height > 30 ? 'multi-line' : 'single-line');
	}