lib.dom.d.ts: IDBKeyPath defined as string instead of string|string[].

TypeScript Version: 2.1.6

Code

    let request = window.indexedDB.open('database', /*version=*/1);

    request.onsuccess = (event: Event) => {
      let db = (event.target as IDBOpenDBRequest).result as IDBDatabase;
      db.createObjectStore('employees', {
        keyPath: ['company_id', 'employee_id']
      });
    };

Expected behavior: Compiles.

Actual behavior:

test_db.ts(26,35): error TS2345: Argument of type '{ keyPath: string[]; }' is not assignable to parameter of type 'IDBObjectStoreParameters | undefined'.
  Type '{ keyPath: string[]; }' is not assignable to type 'IDBObjectStoreParameters'.
    Types of property 'keyPath' are incompatible.
      Type 'string[]' is not assignable to type 'string | undefined'.
        Type 'string[]' is not assignable to type 'string'.

Notes: IndexedDB definition of keypath: https://www.w3.org/TR/IndexedDB/#dfn-key-path

[rtm]

IDBObjectStore.getAll() is also not defined.

[mhegazy]

PRs welcomed. You can find more information about contributing lib.d.ts fixes at https://github.com/Microsoft/TypeScript/blob/master/CONTRIBUTING.md#contributing-libdts-fixes.