fix(material-experimental/mdc-snack-bar): use MDC-based button

Switches the MDC-based snack bar to use the MDC-based button. In general we should
be using the MDC versions of components together, when possible.

Author: crisbeto

src/material-experimental/mdc-snack-bar/BUILD.bazel

@@ -22,6 +22,7 @@ ng_module(
     module_name = "@angular/material-experimental/mdc-snack-bar",
     deps = [
         "//src:dev_mode_types",
+        "//src/material-experimental/mdc-button",
         "//src/material-experimental/mdc-core",
         "//src/material/snack-bar",
         "@npm//@angular/core",
@@ -76,7 +77,10 @@ ng_test_library(
 
 ng_web_test_suite(
     name = "unit_tests",
-    static_files = ["@npm//:node_modules/@material/snackbar/dist/mdc.snackbar.js"],
+    static_files = [
+        "@npm//:node_modules/@material/snackbar/dist/mdc.snackbar.js",
+        "@npm//:node_modules/@material/ripple/dist/mdc.ripple.js",
+    ],
     deps = [
         ":unit_test_sources",
         "//src/material-experimental:mdc_require_config.js",

src/material-experimental/mdc-snack-bar/_snack-bar-theme.scss

@@ -28,6 +28,12 @@
     @include mdc-snackbar-core-styles($query: $mat-theme-styles-query);
   }
 
+  // Usually this color is provided by the `mdc-snackbar-core-styles` mixin, but our styles
+  // to handle unthemed buttons have a higher specificity so we have to re-provide it here.
+  .mat-mdc-snack-bar-container .mat-mdc-snack-bar-action.mdc-snackbar__action {
+    color: $mdc-snackbar-action-ink-color;
+  }
+
   $mdc-snackbar-fill-color: $orig-mdc-snackbar-fill-color !global;
   $mdc-snackbar-label-ink-color: $orig-mdc-snackbar-label-ink-color !global;
   $mdc-snackbar-dismiss-ink-color: $orig-mdc-snackbar-dismiss-ink-color !global;

src/material-experimental/mdc-snack-bar/module.ts

@@ -10,7 +10,7 @@ import {OverlayModule} from '@angular/cdk/overlay';
 import {PortalModule} from '@angular/cdk/portal';
 import {CommonModule} from '@angular/common';
 import {NgModule} from '@angular/core';
-import {MatButtonModule} from '@angular/material/button';
+import {MatButtonModule} from '@angular/material-experimental/mdc-button';
 import {MatCommonModule} from '@angular/material-experimental/mdc-core';
 
 import {MatSimpleSnackBar} from './simple-snack-bar';

src/material-experimental/mdc-snack-bar/snack-bar.spec.ts

@@ -201,7 +201,7 @@ describe('MatSnackBar', () => {
     expect(messageElement.textContent)
         .toContain(simpleMessage, `Expected the snack bar message to be '${simpleMessage}'`);
 
-    let buttonElement = overlayContainerElement.querySelector('button.mat-button')!;
+    let buttonElement = overlayContainerElement.querySelector('button.mat-mdc-button')!;
     expect(buttonElement.tagName)
         .toBe('BUTTON', 'Expected snack bar action label to be a <button>');
     expect((buttonElement.textContent || '').trim())
@@ -224,7 +224,7 @@ describe('MatSnackBar', () => {
     let messageElement = overlayContainerElement.querySelector('mat-mdc-snack-bar-container')!;
     expect(messageElement.textContent)
         .toContain(simpleMessage, `Expected the snack bar message to be '${simpleMessage}'`);
-    expect(overlayContainerElement.querySelector('button.mat-button'))
+    expect(overlayContainerElement.querySelector('button.mat-mdc-button'))
         .toBeNull('Expected the query selection for action label to be null');
   });
 
@@ -363,7 +363,7 @@ describe('MatSnackBar', () => {
         snackBarRef.onAction().subscribe({complete: actionCompleteSpy});
 
         let actionButton =
-            overlayContainerElement.querySelector('button.mat-button') as HTMLButtonElement;
+            overlayContainerElement.querySelector('button.mat-mdc-button') as HTMLButtonElement;
         actionButton.click();
         viewContainerFixture.detectChanges();
         flush();

src/material-experimental/mdc-snack-bar/testing/BUILD.bazel

@@ -34,6 +34,7 @@ ng_web_test_suite(
     name = "unit_tests",
     static_files = [
         "@npm//:node_modules/@material/snackbar/dist/mdc.snackbar.js",
+        "@npm//:node_modules/@material/ripple/dist/mdc.ripple.js",
     ],
     deps = [
         ":unit_tests_lib",