fix   issue

Author: mmalerba

src/lib/select/select.html

@@ -5,7 +5,11 @@
      #origin="cdkOverlayOrigin"
      #trigger>
   <div class="mat-select-value">
-    <ng-container *ngIf="empty">&nbsp;</ng-container>
+    <!--
+      TODO(mmalerba): &nbsp; is currently broken in components with preserveWhitespace: false, so we
+      evaluate it as a JS string binding instead. Change back to &nbsp; once it works again.
+    -->
+    <ng-container *ngIf="empty">{{'\xa0'}}</ng-container>
     <span class="mat-select-value-text" *ngIf="!empty" [ngSwitch]="!!customTrigger">
       <span *ngSwitchDefault>{{ triggerValue }}</span>
       <ng-content select="md-select-trigger, mat-select-trigger" *ngSwitchCase="true"></ng-content>