docs(sidenav): add docs for hasBackdrop (angular#10287)

mmalerba · josephperrott · commit 2fdf93095103 · 2018-03-07T12:36:52.000-08:00
diff --git a/src/lib/progress-spinner/progress-spinner.ts b/src/lib/progress-spinner/progress-spinner.ts
@@ -11,8 +11,6 @@ import {
   ChangeDetectionStrategy,
   Input,
   ElementRef,
-  SimpleChanges,
-  OnChanges,
   ViewEncapsulation,
   Optional,
   Inject,
