Merge pull request #1539 from emberjs/nvp/cleanup-legacy-unused

Cleanup some private API and now-unsupported usage

Author: kategengler

addon/src/-internal/build-registry.ts

@@ -3,7 +3,6 @@ import ApplicationInstance from '@ember/application/instance';
 import Application from '@ember/application';
 import EmberObject from '@ember/object';
 import { Registry } from '@ember/-internals/container';
-import { ComponentLookup } from '@ember/-internals/views';
 
 import type { FullName } from '@ember/owner';
 
@@ -97,9 +96,6 @@ export default function buildRegistry(resolver: Resolver) {
 
   // @ts-ignore: this is private API.
   const fallbackRegistry = Application.buildRegistry(namespace);
-  // TODO: only do this on Ember < 3.13
-  // @ts-ignore: this is private API.
-  fallbackRegistry.register('component-lookup:main', ComponentLookup);
 
   const registry = new Registry({
     fallback: fallbackRegistry,

addon/src/setup-rendering-context.ts

@@ -12,7 +12,6 @@ import getRootElement from './dom/get-root-element.ts';
 import type { Owner } from './build-owner.ts';
 import getTestMetadata from './test-metadata.ts';
 import { runHooks } from './helper-hooks.ts';
-import hasEmberVersion from './has-ember-version.ts';
 import isComponent from './-internal/is-component.ts';
 
 // the built in types do not provide types for @ember/template-compilation
@@ -172,20 +171,6 @@ export function render(
       };
       toplevelView.setOutletState(outletState);
 
-      // Ember's rendering engine is integration with the run loop so that when a run
-      // loop starts, the rendering is scheduled to be done.
-      //
-      // Ember should be ensuring an instance on its own here (the act of
-      // setting outletState should ensureInstance, since we know we need to
-      // render), but on Ember < 3.23 that is not guaranteed.
-      if (!hasEmberVersion(3, 23)) {
-        // SAFETY: this was correct and type checked on the Ember v3 types, but
-        // since the `run` namespace does not exist in Ember v4, this no longer
-        // can be type checked. When (eventually) dropping support for Ember v3,
-        // and therefore for versions before 3.23, this can be removed entirely.
-        (run as any).backburner.ensureInstance();
-      }
-
       // returning settled here because the actual rendering does not happen until
       // the renderer detects it is dirty (which happens on backburner's end
       // hook), see the following implementation details: