As a part of angular#54154, an old parser behavior came up where two-way bindings were parsed by appending `= $event` to the event side. This was problematic, because it allowed some non-writable expressions to be passed into two-way bindings.

These changes introduce a migration that will change the two-way bindings into two separate input/output bindings that represent the old behavior so that in a future version we can throw a parser error for the invalid expressions.

```ts
// Before
@component({
  template: `<input [(ngModel)]="a && b"/>`
})
export class MyComp {}

// After
@component({
  template: `<input [ngModel]="a && b" (ngModelChange)="a && (b = $event)"/>`
})
export class MyComp {}
```