[CLEANUP beta] Only register view keyword helper when legacy enabled

[ghost]

Another part of #11775

Node tests fail.

[rwjblue]

To fix the node tests you need to update this test to something like this:

QUnit.test("It is possible to render a view with a nested {{component}} helper in Node", function(assert) {
    var registry = new Ember.Application.buildRegistry();
    var container = registry.container();

    var View = Ember.Component.extend({
      container: container,
      renderer: new Ember._Renderer(new DOMHelper(new SimpleDOM.Document())),
      layout: compile("<h1>Hello {{#if hasExistence}}{{location}}{{/if}}</h1> <div>{{component 'foo-bar'}}</div>"),
      location: "World",
      hasExistence: true
    });
    var view = View.create();

    registry.register('template:components/foo-bar', compile('<p>The files are *inside* the computer?!</p>'));
    run(view, view.createElement);

    var serializer = new SimpleDOM.HTMLSerializer(SimpleDOM.voidMap);
    assert.ok(serializer.serialize(view.element).match(/<h1>Hello World<\/h1> <div><div id="(.*)" class="ember-view"><p>The files are \*inside\* the computer\?\!<\/p><\/div><\/div>/));
  });

[ghost]

The fix for that test ended up being much simpler than expected.
It still fails :(
Finally fixed it.