feat(material-experimental/button): add to universal app (#16997)

Author: andrewseguin

src/material-experimental/mdc-button/README.md

@@ -1,4 +1,3 @@
 ### TODO
-- Consider supporting button[mat-outlined-button]
-- Add to universal app
+- Consider supporting the selector "button[mat-outlined-button]" for the stroked button
 - Consider if we want to add a "appearance/type" input to button, similar to form field (outline/stroked, flat, raised)

src/universal-app/kitchen-sink-mdc/kitchen-sink-mdc.html

@@ -1,7 +1,16 @@
-<h2>MDC button</h2>
-
-<!-- TODO: Copy kitchen sink examples for mat-button here -->
-Not yet implemented.
+<h2>Button</h2>
+
+<button mat-button>go</button>
+<button mat-icon-button><mat-icon>search</mat-icon></button>
+<button mat-raised-button>go</button>
+<button mat-fab><mat-icon>home</mat-icon></button>
+<button mat-mini-fab><mat-icon>favorite</mat-icon></button>
+
+<a mat-button href="https://google.com">Google</a>
+<a mat-icon-button href="https://google.com"><mat-icon>search</mat-icon></a>
+<a mat-raised-button href="https://google.com">Google</a>
+<a mat-fab href="https://google.com"><mat-icon>home</mat-icon></a>
+<a mat-mini-fab href="https://google.com"><mat-icon>favorite</mat-icon></a>
 
 <h2>MDC card</h2>
 

src/universal-app/kitchen-sink-mdc/kitchen-sink-mdc.ts

@@ -7,6 +7,7 @@ import {MatMenuModule} from '@angular/material-experimental/mdc-menu';
 import {MatRadioModule} from '@angular/material-experimental/mdc-radio';
 import {MatSlideToggleModule} from '@angular/material-experimental/mdc-slide-toggle';
 import {MatTabsModule} from '@angular/material-experimental/mdc-tabs';
+import {MatIconModule} from '@angular/material/icon';
 
 @Component({
   selector: 'kitchen-sink-mdc',
@@ -21,6 +22,7 @@ export class KitchenSinkMdc {
     MatCardModule,
     MatCheckboxModule,
     MatChipsModule,
+    MatIconModule,
     MatMenuModule,
     MatRadioModule,
     MatSlideToggleModule,