separate onerror validation too

addon/src/index.js

@@ -187,8 +187,6 @@ export function setupTestIsolationValidation(delay) {
    @param {Boolean} [options.setupEmberTesting] `false` opts out of the
    default behavior of setting `Ember.testing` to `true` before all tests and
    back to `false` after each test will.
-   @param {Boolean} [options.setupEmberOnerrorValidation] If `false` validation
-   of `Ember.onerror` will be disabled.
    @param {Boolean} [options.setupTestIsolationValidation] If `false` test isolation validation
    will be disabled.
    @param {Number} [options.testIsolationValidationDelay] When using
@@ -209,10 +207,6 @@ export function start(options = {}) {
     setupEmberTesting();
   }
 
-  if (options.setupEmberOnerrorValidation !== false) {
-    setupEmberOnerrorValidation();
-  }
-
   if (
     typeof options.setupTestIsolationValidation !== 'undefined' &&
     options.setupTestIsolationValidation !== false

test-app/tests/test-helper.js

@@ -4,11 +4,12 @@ import * as QUnit from 'qunit';
 import { setApplication } from '@ember/test-helpers';
 import { setup } from 'qunit-dom';
 import { loadTests } from 'ember-qunit/test-loader';
-import { start } from 'ember-qunit';
+import { start, setupEmberOnerrorValidation } from 'ember-qunit';
 
 setApplication(Application.create(config.APP));
 
 setup(QUnit.assert);
 
+setupEmberOnerrorValidation();
 loadTests();
 start();

test-app/types/index.d.ts

@@ -87,6 +87,8 @@ export class QUnitAdapter extends EmberTestAdapter {}
 
 export { module, test, skip, only, todo } from 'qunit';
 
+export function setupEmberOnerrorValidation(): void;
+
 interface QUnitStartOptions {
   /**
    * If `false` tests will not be loaded automatically.
@@ -116,11 +118,6 @@ interface QUnitStartOptions {
    */
   setupEmberTesting?: boolean | undefined;
 
-  /**
-   * If `false` validation of `Ember.onerror` will be disabled.
-   */
-  setupEmberOnerrorValidation?: boolean | undefined;
-
   /**
    * If `false` test isolation validation will be disabled.
    */