Remove duplicate code from BVC shutdown method

Change-Id: I1120f0b982b28f7854098fbdd91190ccd9c82a62
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1614964Reviewed-by: edchin <edchin@chromium.org>
Commit-Queue: Mohammad Refaat <mrefaat@chromium.org>
Cr-Commit-Position: refs/heads/master@{#660897}

ios/chrome/browser/ui/browser_view/browser_view_controller.mm

@@ -1447,8 +1447,6 @@ NSString* const kBrowserViewControllerSnackbarCategory =
   [self.commandDispatcher stopDispatchingToTarget:self];
   self.commandDispatcher = nil;
 
-  [self.tabStripCoordinator stop];
-  self.tabStripCoordinator = nil;
   [self.primaryToolbarCoordinator stop];
   self.primaryToolbarCoordinator = nil;
   [self.secondaryToolbarContainerCoordinator stop];
@@ -1458,7 +1456,6 @@ NSString* const kBrowserViewControllerSnackbarCategory =
   [_downloadManagerCoordinator stop];
   _downloadManagerCoordinator = nil;
   self.toolbarInterface = nil;
-  self.tabStripView = nil;
   [self.infobarContainerCoordinator stop];
   self.infobarContainerCoordinator = nil;
   // SideSwipeController is a tab model observer, so it needs to stop observing