build: fix error with latest MDC version (#21089)

The slider adapter was updated on MDC's side which is breaking the build.

Author: crisbeto

package.json

@@ -62,7 +62,7 @@
     "@types/youtube": "^0.0.38",
     "@webcomponents/custom-elements": "^1.1.0",
     "core-js": "^2.6.9",
-    "material-components-web": "9.0.0-canary.419e03572.0",
+    "material-components-web": "9.0.0-canary.30c11bfc2.0",
     "rxjs": "^6.5.3",
     "rxjs-tslint-rules": "^4.33.1",
     "systemjs": "0.19.43",

src/material-experimental/mdc-slider/slider.ts

@@ -258,7 +258,12 @@ export class MatSlider implements AfterViewInit, OnChanges, OnDestroy, ControlVa
     removeTrackActiveStyleProperty: (_propertyName: string) => {},
     emitDragStartEvent: (_value: number, _thumb: Thumb) => {},
     emitDragEndEvent: (_value: number, _thumb: Thumb) => {},
-    getValueToAriaValueTextFn: () => null
+    getValueToAriaValueTextFn: () => null,
+    getInputValue: () => '',
+    setInputValue: (_value: string, _thumb: Thumb) => {},
+    getInputAttribute: (_attribute: string, _thumb: Thumb) => null,
+    setInputAttribute: (_attribute: string, _value: string) => {},
+    removeInputAttribute: (_attribute: string) => {}
   };
 
   /** Instance of the MDC slider foundation for this slider. */