{{render}} helper no longer able to bubble actions without legacy controller addon.

[rwjblue]

Given the following example:

{{! index template}}
{{render 'some-name' someModel}}

<p>{{this}} - {{this.target}} - {{this.parentController}}</p>

<button {{action 'thingInApplicationRoute'}}>
  Should hit route!
</button>

In Ember 2.0 and 2.1, that action would bubble properly to the router (and then on to the application route). In Ember 2.2 and above this bubbling behavior is no longer present, unless the ember-legacy-controller addon is in use.

The root cause is that we no longer create the controller template local unless that addon is present (this was done in #12289 which landed in 2.2), however the {{render helper still grabs the controller local to specify target for the newly created controller instance (the controller local is looked up here and passed as the target here and here).

2.1 demo
2.2 demo
2.3 demo
2.4 demo

Working 2.4 demo with the legacy controller flag enabled.

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The fix is to fallback to the previously looked up router instance if the parentController variable is undefined. PR will be incoming shortly....

[rwjblue]

Updated with a bunch of demos.