bug(MatTabGroup): StaticInjectorError thrown when using MatTabGroup with wrapper component

Reproduction

See this Stackblitz

Create a component that includes a MatTabGroup whose MatTab come inside ng-content

<mat-tab-group #tabGroup>
     <ng-content></ng-content>
</mat-tab-group>

Expected Behavior

The MatTabGroup should not give an error, as it was the case with Angular 10 / Angular Material 10. See this stackblitz for a working example with Angular 10 / Angular Material 10

Actual Behavior

The following error is thrown:

Error: StaticInjectorError(AppModule)[MatTab -> InjectionToken MAT_TAB_GROUP]:
StaticInjectorError(Platform: core)[MatTab -> InjectionToken MAT_TAB_GROUP]:
NullInjectorError: No provider for InjectionToken MAT_TAB_GROUP!

Environment

• Angular: 11.1.1
• CDK/Material: 11.1.1
• Browser(s): Tested in Chrome and Firefox
• Operating System (e.g. Windows, macOS, Ubuntu): Tested on macOS and Ubuntu

[Brutusn]

I ‘fixed’ the issue by providing the MAT_TAB_GROUP token in the wrapper component:

providers: [
	{
		provide: MAT_TAB_GROUP,
		useValue: undefined,
	},
],

[crisbeto]

Merging the fix itself isn’t that difficult, but releasing the changes and updating the docs takes a while.