fix(multiple): fix disabled label style (#25181)

MDC does not set the disabled text color on the label for the checkbox,
radio, or switch. This change applies it on the Angular Material side.

(cherry picked from commit 3e9bd1e)

Author: mmalerba

src/material-experimental/mdc-checkbox/_checkbox-theme.scss

@@ -33,6 +33,7 @@
   $primary: mat.get-color-from-palette(map.get($config, primary));
   $accent: mat.get-color-from-palette(map.get($config, accent));
   $warn: mat.get-color-from-palette(map.get($config, warn));
+  $foreground: map.get($config, foreground);
 
   @include mdc-helpers.mat-using-mdc-theme($config) {
     .mat-mdc-checkbox {
@@ -65,6 +66,11 @@
         @include _selected-ripple-colors($warn, error);
       }
     }
+
+    .mat-mdc-checkbox-disabled label {
+      // MDC should set the disabled color on the label, but doesn't, so we do it here instead.
+      color: mat.get-color-from-palette($foreground, disabled-text);
+    }
   }
 }
 

src/material-experimental/mdc-radio/_radio-theme.scss

@@ -22,6 +22,7 @@
   $primary: mat.get-color-from-palette(map.get($config, primary));
   $accent: mat.get-color-from-palette(map.get($config, accent));
   $warn: mat.get-color-from-palette(map.get($config, warn));
+  $foreground: map.get($config, foreground);
 
   @include mdc-helpers.mat-using-mdc-theme($config) {
     $on-surface: rgba(mdc-theme-color.$on-surface, 0.54);
@@ -47,6 +48,11 @@
 
       --mat-mdc-radio-ripple-color: #{mdc-theme-color.prop-value(on-surface)};
 
+      // MDC should set the disabled color on the label, but doesn't, so we do it here instead.
+      .mdc-radio--disabled + label {
+        color: mat.get-color-from-palette($foreground, disabled-text);
+      }
+
       &.mat-primary {
         @include _color-palette($primary);
       }

src/material-experimental/mdc-slide-toggle/_slide-toggle-theme.scss

@@ -74,6 +74,7 @@
   $accent: mat.get-color-from-palette(map.get($config, accent));
   $warn: mat.get-color-from-palette(map.get($config, warn));
   $is-dark: map.get($config, is-dark);
+  $foreground: map.get($config, foreground);
 
   @include mdc-helpers.mat-using-mdc-theme($config) {
     // MDC's switch doesn't support a `color` property. We add support
@@ -82,6 +83,11 @@
       @include mdc-form-field.core-styles($query: mdc-helpers.$mat-theme-styles-query);
       @include mdc-switch-theme.theme(_get-theme-base-map($is-dark));
 
+      // MDC should set the disabled color on the label, but doesn't, so we do it here instead.
+      .mdc-switch--disabled + label {
+        color: mat.get-color-from-palette($foreground, disabled-text);
+      }
+
       &.mat-primary {
         @include mdc-switch-theme.theme(_get-theme-color-map($primary));
       }