src/vs/workbench/contrib/scm/browser/dirtydiffDecorator.ts/DirtyDiffWidget/_applyTheme
class DirtyDiffWidget:	private _applyTheme(theme: IColorTheme) {
		const borderColor = theme.getColor(peekViewBorder) || Color.transparent;
		this.style({
			arrowColor: borderColor,
			frameColor: borderColor,
			headerBackgroundColor: theme.getColor(peekViewTitleBackground) || Color.transparent,
			primaryHeadingColor: theme.getColor(peekViewTitleForeground),
			secondaryHeadingColor: theme.getColor(peekViewTitleInfoForeground)
		});
	}