Remove invalid DCHECK in [CRWSessionController addPendingItem].

ios/web/navigation/crw_session_controller.mm

Index: ios/web/navigation/crw_session_controller.mm
diff --git a/ios/web/navigation/crw_session_controller.mm b/ios/web/navigation/crw_session_controller.mm
index 2dfb1c57132886b112ca575a47edc664f6168acb..cf5175e1673d9b538cc846748aede176d338b9c8 100644
--- a/ios/web/navigation/crw_session_controller.mm
+++ b/ios/web/navigation/crw_session_controller.mm
@@ -287,10 +287,6 @@ - (void)addPendingItem:(const GURL&)url
              initiationType:(web::NavigationInitiationType)initiationType
     userAgentOverrideOption:(web::NavigationManager::UserAgentOverrideOption)
                                 userAgentOverrideOption {
-  // Server side redirects are handled by updating existing pending item instead
-  // of adding a new item.
-  DCHECK((trans & ui::PAGE_TRANSITION_SERVER_REDIRECT) == 0);
-
   [self discardTransientItem];
   self.pendingItemIndex = -1;