[BUGFIX beta] Expose ownerInjection method on ContainerProxy.

The `ember-container-inject-owner` feature provides a public API for
accessing various container/registry functions. Unfortunately, creating
an instance that has access to the same owner is a somewhat annoying
API compared to what we would do today.

In Ember 2.2 you would often do this (though it still uses private API):

```js
User.create({
 container: this.container,
 username: 'John'
});
```

But in 2.3.0-beta.1 to do roughly the same thing, you would have to do:

```js
var options = { username: 'John' };
setOwner(options, getOwner(this));

User.create(options);
```

This is definitely less ergonomic for a perfectly supported case.  With
the changes added here, you would use the following:

```js
User.create(
 getOwner(this).ownerInjection(),
 { username: 'John' }
);
```

packages/container/lib/container.js

@@ -2,7 +2,7 @@ import Ember from 'ember-metal/core';
 import { assert, deprecate } from 'ember-metal/debug';
 import dictionary from 'ember-metal/dictionary';
 import isEnabled from 'ember-metal/features';
-import { setOwner } from './owner';
+import { setOwner, OWNER } from './owner';
 import { buildFakeContainerWithDeprecations } from 'ember-runtime/mixins/container_proxy';
 
 /**
@@ -159,6 +159,18 @@ Container.prototype = {
     } else {
       resetCache(this);
     }
+  },
+
+  /**
+   Returns an object that can be used to provide an owner to a
+   manually created instance.
+
+   @private
+   @method ownerInjection
+   @returns { Object }
+  */
+  ownerInjection() {
+    return { [OWNER]: this.owner };
   }
 };
 

packages/container/tests/container_test.js

@@ -1,7 +1,7 @@
 import Ember from 'ember-metal/core';
 import Registry from 'container/registry';
 import factory from 'container/tests/test-helpers/factory';
-import { getOwner } from 'container/owner';
+import { getOwner, OWNER } from 'container/owner';
 import isEnabled from 'ember-metal/features';
 
 var originalModelInjections;
@@ -519,6 +519,16 @@ QUnit.test('Lazy injection validations are cached', function() {
   container.lookup('apple:main');
 });
 
+QUnit.test('An object with its owner pre-set should be returned from ownerInjection', function() {
+  let owner = { };
+  var registry = new Registry();
+  var container = registry.container({ owner });
+
+  let result = container.ownerInjection();
+
+  equal(result[OWNER], owner, 'owner is properly included');
+});
+
 if (isEnabled('ember-container-inject-owner')) {
   QUnit.test('A deprecated `container` property is appended to every object instantiated from an extendable factory', function() {
     let registry = new Registry();

packages/ember-runtime/lib/mixins/container_proxy.js

@@ -23,6 +23,27 @@ export default Mixin.create({
    */
   __container__: null,
 
+  /**
+   Returns an object that can be used to provide an owner to a
+   manually created instance.
+
+   Example:
+
+   ```
+   let owner = Ember.getOwner(this);
+
+   User.create(
+     owner.ownerInjection(),
+     { username: 'rwjblue' }
+   )
+   ```
+
+   @public
+   @method ownerInjection
+   @return {Object}
+  */
+  ownerInjection: containerAlias('ownerInjection'),
+
   /**
    Given a fullName return a corresponding instance.
 

packages/ember-runtime/tests/mixins/container_proxy_test.js

@@ -0,0 +1,24 @@
+import { OWNER } from 'container/owner';
+import Registry from 'container/registry';
+import Container from 'container/container';
+import ContainerProxy from 'ember-runtime/mixins/container_proxy';
+import EmberObject from 'ember-runtime/system/object';
+
+QUnit.module('ember-runtime/mixins/container_proxy', {
+  setup() {
+    this.Owner = EmberObject.extend(ContainerProxy);
+    this.instance = this.Owner.create();
+
+    let registry = new Registry();
+
+    this.instance.__container__ = new Container(registry, {
+      owner: this.instance
+    });
+  }
+});
+
+QUnit.test('provides ownerInjection helper method', function(assert) {
+  let result = this.instance.ownerInjection();
+
+  assert.equal(result[OWNER], this.instance, 'returns an object with the OWNER symbol');
+});