[CRD iOS] Remove workaround for excessive host list padding

Given that fixes in both MDC and GoogleKit have already been rolled into
Chromium, the workaround is no longer needed.

Bug: 766892
Change-Id: I2ba2b09c399bc845f867057c261125cbcc3444ea
Reviewed-on: https://chromium-review.googlesource.com/740879Reviewed-by: Jamie Walch <jamiewalch@chromium.org>
Commit-Queue: Yuwei Huang <yuweih@chromium.org>
Cr-Commit-Position: refs/heads/master@{#512589}

remoting/ios/app/remoting_view_controller.mm

@@ -369,15 +369,6 @@ animationControllerForDismissedController:(UIViewController*)dismissed {
       contentViewController.collectionView;
   self.contentViewController = contentViewController;
   self.contentViewController.view.frame = self.view.bounds;
-
-  if (@available(iOS 11.0, *)) {
-    // TODO(crbug.com/766892): This is a workaround for material component bug
-    // https://github.com/material-components/material-components-ios/issues/1962
-    // Remove once it is resolved.
-    self.headerViewController.headerView.trackingScrollView
-        .contentInsetAdjustmentBehavior =
-        UIScrollViewContentInsetAdjustmentNever;
-  }
 }
 
 - (void)handleHostListFetchFailure:(HostListFetchFailureReason)reason {