src/vs/platform/contextkey/common/contextkey.ts/ContextKeyEqualsExpr/create
class ContextKeyEqualsExpr:	public static create(key: string, value: any, negated: ContextKeyExpression | null = null): ContextKeyExpression {
		if (typeof value === 'boolean') {
			return (value ? ContextKeyDefinedExpr.create(key, negated) : ContextKeyNotExpr.create(key, negated));
		}
		const constantValue = CONSTANT_VALUES.get(key);
		if (typeof constantValue === 'boolean') {
			const trueValue = constantValue ? 'true' : 'false';
			return (value === trueValue ? ContextKeyTrueExpr.INSTANCE : ContextKeyFalseExpr.INSTANCE);
		}
		return new ContextKeyEqualsExpr(key, value, negated);
	}