make createRecord sync and remove unnecessary run usage in tests

[runspired]

refactor all the test usage or run-wrapping for createRecord, we really should run prettier

resolves #5247 because I <3 @rwjblue

[sly7-7]

Any idea about the failing test against ember 2-12 ?

[runspired]

@sly7-7 I'm not sure why ember 2.12 specifically does not pass; however, I dug into the test and realized that it was a bogus test. After rewriting it to test what it claims to be writing I find that this feature has been broken for a very very long time.

test('it is possible to filter created records by isReloading', function(assert) {
  customAdapter(env, DS.Adapter.extend({
    findRecord(store, type, id, snapshot) {
      return {
        data: {
          id: 1,
          type: 'person',
          attributes: {
            name: 'Tom Dalle'
          }
        }
      };
    }
  }));

  let filter = store.filter('person', person => {
    return !person.get('isReloading');
  });

  let person = store.createRecord('person', {
    id: '1',
    name: 'Tom Dale'
  });

  assert.equal(person.get('isReloading'), false, 'The person is not reloading');
  assert.equal(filter.get('length'), 1, 'the filter correctly returned a available record');

  run(() => {
    person.reload();
    assert.equal(person.get('isReloading'), true, 'The person is reloading');
    assert.equal(filter.get('length'), 0, 'the filter correctly removes an isReloading record');
  });

  assert.equal(person.get('isReloading'), false, 'The person is done reloading');
  assert.equal(filter.get('length'), 1, 'the filter correctly returned a reloaded record');
});

The assertion for length 0 will not trigger even though the state at that point is confirmed to be isReloading. We don't really support filters anymore, especially in this situation where we would have to be overly noisy (bad for perf) for all record arrays for an edge case. Someone desiring this behavior would be much better suited to filter via @each.isReloading. I'm removing this test.

[runspired]

seems I have some async test leaks to find