fix(typings): update typings to support more strict typings in RxJS 6.3.2 (#12979)

Author: benlesh

src/lib/progress-bar/progress-bar.ts

@@ -191,7 +191,7 @@ export class MatProgressBar extends _MatProgressBarMixinBase implements CanColor
       // instead only on the animation that we care about (primary value bar's transitionend)
       this._ngZone.runOutsideAngular((() => {
         this._animationEndSubscription =
-            fromEvent(this._primaryValueBar.nativeElement, 'transitionend')
+            fromEvent<TransitionEvent>(this._primaryValueBar.nativeElement, 'transitionend')
             .pipe(filter(((e: TransitionEvent) =>
               e.target === this._primaryValueBar.nativeElement)))
             .subscribe(_ => this._ngZone.run(() => this.emitAnimationEnd()));

src/lib/table/table-data-source.ts

@@ -200,11 +200,11 @@ export class MatTableDataSource<T> extends DataSource<T> {
     // The `sortChange` and `pageChange` acts as a signal to the combineLatests below so that the
     // pipeline can progress to the next step. Note that the value from these streams are not used,
     // they purely act as a signal to progress in the pipeline.
-    const sortChange: Observable<Sort|null> = this._sort ?
-        merge<Sort>(this._sort.sortChange, this._sort.initialized) :
+    const sortChange: Observable<Sort|null|void> = this._sort ?
+        merge<Sort|void>(this._sort.sortChange, this._sort.initialized) :
         observableOf(null);
-    const pageChange: Observable<PageEvent|null> = this._paginator ?
-        merge<PageEvent>(this._paginator.page, this._paginator.initialized) :
+    const pageChange: Observable<PageEvent|null|void> = this._paginator ?
+        merge<PageEvent|void>(this._paginator.page, this._paginator.initialized) :
         observableOf(null);
 
     const dataStream = this._data;