fix(material/dialog): mat-dialog-title should work under OnPush `…

…viewContainerRef`

The `mat-dialog-title` directive updates state in a microtask and should
call `ChangeDetectorRef.markForCheck`. Failing to do this will cause the
component tree to not be checked if it lives under an `OnPush` component
that has not otherwise been marked for check.

src/material/dialog/dialog-content-directives.ts

@@ -7,8 +7,10 @@
  */
 
 import {
+  ChangeDetectorRef,
   Directive,
   ElementRef,
+  inject,
   Input,
   OnChanges,
   OnDestroy,
@@ -102,6 +104,7 @@ export class MatDialogClose implements OnInit, OnChanges {
 })
 export class MatDialogTitle implements OnInit, OnDestroy {
   @Input() id: string = `mat-mdc-dialog-title-${dialogElementUid++}`;
+  private readonly changeDetectorRef = inject(ChangeDetectorRef);
 
   constructor(
     // The dialog title directive is always used in combination with a `MatDialogRef`.
@@ -121,6 +124,7 @@ export class MatDialogTitle implements OnInit, OnDestroy {
         // Note: we null check the queue, because there are some internal
         // tests that are mocking out `MatDialogRef` incorrectly.
         this._dialogRef._containerInstance?._ariaLabelledByQueue?.push(this.id);
+        this.changeDetectorRef.markForCheck();
       });
     }
   }

src/material/dialog/dialog.spec.ts

@@ -49,6 +49,7 @@ import {
   MatDialogRef,
   MAT_DIALOG_DATA,
   MAT_DIALOG_DEFAULT_OPTIONS,
+  MatDialogTitle,
 } from './index';
 import {CLOSE_ANIMATION_DURATION, OPEN_ANIMATION_DURATION} from './dialog-container';
 
@@ -1617,6 +1618,55 @@ describe('MDC-based MatDialog', () => {
       runContentElementTests();
     });
 
+    it('should set the aria-labelledby attribute to the id of the title under OnPush host', fakeAsync(() => {
+      @Component({
+        standalone: true,
+        imports: [MatDialogTitle],
+        template: `<h1 mat-dialog-title>This is the first title</h1>`,
+      })
+      class DialogCmp {}
+
+      @Component({
+        template: '',
+        selector: 'child',
+        standalone: true,
+      })
+      class Child {
+        constructor(
+          readonly viewContainerRef: ViewContainerRef,
+          readonly dialog: MatDialog,
+        ) {}
+
+        open() {
+          this.dialog.open(DialogCmp, {viewContainerRef: this.viewContainerRef});
+        }
+      }
+
+      @Component({
+        standalone: true,
+        imports: [Child],
+        template: `<child></child>`,
+        changeDetection: ChangeDetectionStrategy.OnPush,
+      })
+      class OnPushHost {
+        @ViewChild(Child, {static: true}) child: Child;
+      }
+
+      const hostFixture = TestBed.createComponent(OnPushHost);
+      hostFixture.componentInstance.child.open();
+      hostFixture.autoDetectChanges();
+      flush();
+
+      const overlayContainer = TestBed.inject(OverlayContainer);
+      const title = overlayContainer.getContainerElement().querySelector('[mat-dialog-title]')!;
+      const container = overlayContainerElement.querySelector('mat-dialog-container')!;
+
+      expect(title.id).withContext('Expected title element to have an id.').toBeTruthy();
+      expect(container.getAttribute('aria-labelledby'))
+        .withContext('Expected the aria-labelledby to match the title id.')
+        .toBe(title.id);
+    }));
+
     function runContentElementTests() {
       it('should close the dialog when clicking on the close button', fakeAsync(() => {
         expect(overlayContainerElement.querySelectorAll('.mat-mdc-dialog-container').length).toBe(