feat(material-expeirmental/mdc-list): add support for focus/hover states

and ripples

Author: mmalerba

src/material-experimental/mdc-list/action-list.ts

@@ -23,4 +23,6 @@ import {MatListBase} from './list-base';
     {provide: MatListBase, useExisting: MatActionList},
   ]
 })
-export class MatActionList extends MatListBase {}
+export class MatActionList extends MatListBase {
+  _hasRipple = true;
+}

src/material-experimental/mdc-list/list-base.ts

@@ -21,7 +21,7 @@ import {Subscription} from 'rxjs';
 import {startWith} from 'rxjs/operators';
 
 @Directive()
-export class MatListBase {
+export abstract class MatListBase {
   // @HostBinding is used in the class as it is expected to be extended. Since @Component decorator
   // metadata is not inherited by child classes, instead the host binding data is defined in a way
   // that can be inherited.

src/material-experimental/mdc-list/nav-list.ts

@@ -33,4 +33,6 @@ import {MatListBase} from './list-base';
     {provide: MatList, useExisting: MatNavList},
   ]
 })
-export class MatNavList extends MatListBase {}
+export class MatNavList extends MatListBase {
+  _hasRipple = true;
+}