src/vs/workbench/services/themes/common/themeExtensionPoints.ts/ThemeRegistry/findThemeByExtensionLocation
class ThemeRegistry:	public findThemeByExtensionLocation(extLocation: URI | undefined): T[] {
		if (extLocation) {
			return this.getThemes().filter(t => t.location && resources.isEqualOrParent(t.location, extLocation));
		}
		return [];
	}