(Set)IsOverridingUserAgent should be called on VisibleItem

ios/web/navigation/crw_session_controller.mm

 // Copyright 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #import "ios/web/navigation/crw_session_controller.h"
 
 #include <stddef.h>
 
 #include <algorithm>
 #include <utility>
@@ skipping 56 matching lines @@
   // The window name associated with the session.
   NSString* _windowName;
 
    // Stores the certificate policies decided by the user.
   CRWSessionCertificatePolicyManager* _sessionCertificatePolicyManager;
 
   // The timestamp of the last time this tab is visited, represented in time
   // interval since 1970.
   NSTimeInterval _lastVisitedTimestamp;
 
-  // If |YES|, override |currentEntry.useDesktopUserAgent| and create the
-  // pending entry using the desktop user agent.
-  BOOL _useDesktopUserAgentForNextPendingItem;
-
   // The browser state associated with this CRWSessionController;
   web::BrowserState* _browserState;  // weak
 
   // Time smoother for navigation entry timestamps; see comment in
   // navigation_controller_impl.h
   web::TimeSmoother _timeSmoother;
 }
 
 // Redefine as readwrite.
 @property(nonatomic, readwrite, assign) NSInteger currentNavigationIndex;
@@ skipping 398 matching lines @@
   DCHECK(navigationItem);
   navigationItem->SetTimestamp(
       _timeSmoother.GetSmoothedTime(base::Time::Now()));
 }
 
 - (void)pushNewItemWithURL:(const GURL&)URL
                stateObject:(NSString*)stateObject
                 transition:(ui::PageTransition)transition {
   DCHECK(![self pendingEntry]);
   DCHECK([self currentEntry]);
-  web::NavigationItem* currentItem = [self currentEntry].navigationItem;
+
+  web::NavigationItem* lastCommittedItem =
+      self.lastCommittedEntry.navigationItem;
   CHECK(web::history_state_util::IsHistoryStateChangeValid(
-      currentItem->GetURL(), URL));
-  web::Referrer referrer(currentItem->GetURL(), web::ReferrerPolicyDefault);
+      lastCommittedItem->GetURL(), URL));
 
+  web::Referrer referrer(lastCommittedItem->GetURL(),
+                         web::ReferrerPolicyDefault);
   base::scoped_nsobject<CRWSessionEntry> pushedEntry([self
       sessionEntryWithURL:URL
                  referrer:referrer
                transition:transition
            initiationType:web::NavigationInitiationType::USER_INITIATED]);
 
   web::NavigationItemImpl* pushedItem = [pushedEntry navigationItemImpl];
-  pushedItem->SetIsOverridingUserAgent(currentItem->IsOverridingUserAgent());
+  pushedItem->SetIsOverridingUserAgent(
+      lastCommittedItem->IsOverridingUserAgent());
   pushedItem->SetSerializedStateObject(stateObject);
   pushedItem->SetIsCreatedFromPushState(true);
-  web::SSLStatus& sslStatus = [self currentEntry].navigationItem->GetSSL();
-  pushedEntry.get().navigationItem->GetSSL() = sslStatus;
+  pushedItem->GetSSL() = lastCommittedItem->GetSSL();
 
   [self clearForwardItems];
   // Add the new entry at the end.
   [_entries addObject:pushedEntry];
   _previousNavigationIndex = _currentNavigationIndex;
   self.currentNavigationIndex = [_entries count] - 1;
 
   if (_navigationManager)
     _navigationManager->OnNavigationItemCommitted();
 }
@@ skipping 199 matching lines @@
 }
 
 - (web::NavigationItemList)itemListForEntryList:(NSArray*)entries {
   web::NavigationItemList list(entries.count);
   for (size_t index = 0; index < entries.count; ++index)
     list[index] = [entries[index] navigationItem];
   return list;
 }
 
 @end