feat(ivy): add ngcc ivy switch (#25238)

Provides a runtime and compile time switch for ivy including
`ApplicationRef.bootstrapModule`.

This is done by naming the symbols such that `ngcc` (angular
Compatibility compiler) can rename symbols in such a way that running
`ngcc` command will switch the `@angular/core` module from `legacy` to
`ivy` mode.

This is done as follows:

```
const someToken__PRE_NGCC__ = ‘legacy mode’;
const someToken__POST_NGCC__ = ‘ivy mode’;

export someSymbol = someToken__PRE_NGCC__;
```

The `ngcc` will search for any token which ends with `__PRE_NGCC__`
and replace it with `__POST_NGCC__`. This allows the `@angular/core`
package to be rewritten to ivy mode post `ngcc` execution.

PR Close #25238

packages/core/src/render3/util.ts

@@ -5,7 +5,7 @@
  * Use of this source code is governed by an MIT-style license that can be
  * found in the LICENSE file at https://angular.io/license
  */
-import {devModeEqual} from '../change_detection/change_detection';
+import {devModeEqual} from '../change_detection/change_detection_util';
 import {assertLessThan} from './assert';
 import {LElementNode} from './interfaces/node';
 import {HEADER_OFFSET, LViewData} from './interfaces/view';