fix(material/dialog): breaking changes for v20

Removes the deprecated symbols for v20 from the dialog.

BREAKING CHANGE:
* `MAT_DIALOG_SCROLL_STRATEGY_PROVIDER` has been removed.
* `MAT_DIALOG_SCROLL_STRATEGY_PROVIDER_FACTORY` has been removed.

Author: crisbeto

src/material/dialog/dialog.ts

@@ -44,28 +44,6 @@ export const MAT_DIALOG_SCROLL_STRATEGY = new InjectionToken<() => ScrollStrateg
   },
 );
 
-/**
- * @docs-private
- * @deprecated No longer used. To be removed.
- * @breaking-change 19.0.0
- */
-export function MAT_DIALOG_SCROLL_STRATEGY_PROVIDER_FACTORY(
-  overlay: Overlay,
-): () => ScrollStrategy {
-  return () => overlay.scrollStrategies.block();
-}
-
-/**
- * @docs-private
- * @deprecated No longer used. To be removed.
- * @breaking-change 19.0.0
- */
-export const MAT_DIALOG_SCROLL_STRATEGY_PROVIDER = {
-  provide: MAT_DIALOG_SCROLL_STRATEGY,
-  deps: [Overlay],
-  useFactory: MAT_DIALOG_SCROLL_STRATEGY_PROVIDER_FACTORY,
-};
-
 /**
  * Service to open Material Design modal dialogs.
  */

tools/public_api_guard/material/dialog.md

@@ -25,7 +25,6 @@ import { Observable } from 'rxjs';
 import { OnChanges } from '@angular/core';
 import { OnDestroy } from '@angular/core';
 import { OnInit } from '@angular/core';
-import { Overlay } from '@angular/cdk/overlay';
 import { ScrollStrategy } from '@angular/cdk/overlay';
 import { SimpleChanges } from '@angular/core';
 import { Subject } from 'rxjs';
@@ -66,16 +65,6 @@ export const MAT_DIALOG_DEFAULT_OPTIONS: InjectionToken<MatDialogConfig<any>>;
 // @public
 export const MAT_DIALOG_SCROLL_STRATEGY: InjectionToken<() => ScrollStrategy>;
 
-// @public @deprecated
-export const MAT_DIALOG_SCROLL_STRATEGY_PROVIDER: {
-    provide: InjectionToken<() => ScrollStrategy>;
-    deps: (typeof Overlay)[];
-    useFactory: typeof MAT_DIALOG_SCROLL_STRATEGY_PROVIDER_FACTORY;
-};
-
-// @public @deprecated
-export function MAT_DIALOG_SCROLL_STRATEGY_PROVIDER_FACTORY(overlay: Overlay): () => ScrollStrategy;
-
 // @public
 export class MatDialog implements OnDestroy {
     constructor(...args: unknown[]);