src/vs/workbench/services/textMate/common/TMHelper.ts/ThemeRule/_matches
class ThemeRule:	private static _matches(selectorScope: string, selectorParentScopes: string[], scope: string, parentScopes: string[]): boolean {
		if (!this._matchesOne(selectorScope, scope)) {
			return false;
		}

		let selectorParentIndex = selectorParentScopes.length - 1;
		let parentIndex = parentScopes.length - 1;
		while (selectorParentIndex >= 0 && parentIndex >= 0) {
			if (this._matchesOne(selectorParentScopes[selectorParentIndex], parentScopes[parentIndex])) {
				selectorParentIndex--;
			}
			parentIndex--;
		}

		if (selectorParentIndex === -1) {
			return true;
		}
		return false;
	}