Change return type of Tab -navigationManager.

ios/chrome/browser/tabs/tab.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/chrome/browser/tabs/tab.h"
 
 #import <CoreLocation/CoreLocation.h>
 #import <UIKit/UIKit.h>
 
 #include <utility>
@@ skipping 855 matching lines @@
   if (![self.webController isViewAlive] && [parentTabModel_ tabUsageRecorder]) {
     [parentTabModel_ tabUsageRecorder]->RecordPageLoadStart(self);
   }
   return self.webState ? self.webState->GetView() : nil;
 }
 
 - (UIView*)viewForPrinting {
   return self.webController.viewForPrinting;
 }
 
-- (NavigationManagerImpl*)navigationManager {
-  if (!webStateImpl_)
-    return nil;
-  return &(webStateImpl_->GetNavigationManagerImpl());
+- (web::NavigationManager*)navigationManager {
+  return webStateImpl_ ? webStateImpl_->GetNavigationManager() : nullptr;
+}
+
+- (web::NavigationManagerImpl*)navigationManagerImpl {
+  return webStateImpl_ ? &(webStateImpl_->GetNavigationManagerImpl()) : nullptr;
 }
 
 - (id<StoreKitLauncher>)storeKitLauncher {
   return storeKitLauncher_.get();
 }
 
 - (void)setStoreKitLauncher:(id<StoreKitLauncher>)storeKitLauncher {
   storeKitLauncher_.reset(storeKitLauncher);
 }
 
 // Swap out the existing session history with a new list of navigations. Forces
 // the tab to reload to update the UI accordingly. This is ok because none of
 // the session history is stored in the tab; it's always fetched through the
 // navigation manager.
 - (void)replaceHistoryWithNavigations:
             (const std::vector<sessions::SerializedNavigationEntry>&)navigations
                          currentIndex:(NSInteger)currentIndex {
   std::vector<std::unique_ptr<web::NavigationItem>> items =
       sessions::IOSSerializedNavigationBuilder::ToNavigationItems(navigations);
-  [self navigationManager]->ReplaceSessionHistory(std::move(items),
-                                                  currentIndex);
+  [self navigationManagerImpl]->ReplaceSessionHistory(std::move(items),
+                                                      currentIndex);
   [self didReplaceSessionHistory];
 
   [self.webController loadCurrentURL];
 }
 
 - (void)didReplaceSessionHistory {
   // Replace fullScreenController_ with a new sessionID  when the navigation
   // manager changes.
   // TODO(crbug.com/661666): Consider just updating sessionID and not replacing
   // |fullScreenController_|.
@@ skipping 356 matching lines @@
 }
 
 - (void)dismissModals {
   [openInController_ disable];
   [self.webController dismissModals];
 }
 
 - (web::NavigationItem*)currentNavigationItem {
   if (![self navigationManager])
     return nil;
-  return [[self navigationManager]->GetSessionController() currentItem];
+  return [[self navigationManagerImpl]->GetSessionController() currentItem];
 }
 
 - (void)setShouldObserveInfoBarManager:(BOOL)shouldObserveInfoBarManager {
   tabInfoBarObserver_->SetShouldObserveInfoBarManager(
       shouldObserveInfoBarManager);
 }
 
 - (void)setShouldObserveFaviconChanges:(BOOL)shouldObserveFaviconChanges {
   if (shouldObserveFaviconChanges) {
     favicon::FaviconDriver* faviconDriver =
@@ skipping 30 matching lines @@
 
 - (BOOL)canGoForward {
   return self.navigationManager && self.navigationManager->CanGoForward();
 }
 
 - (void)goToItem:(const web::NavigationItem*)item {
   DCHECK(item);
 
   if (self.navigationManager) {
     CRWSessionController* sessionController =
-        self.navigationManager->GetSessionController();
+        [self navigationManagerImpl]->GetSessionController();
     NSInteger itemIndex = [sessionController indexOfItem:item];
     DCHECK_NE(itemIndex, NSNotFound);
     self.navigationManager->GoToIndex(itemIndex);
   }
 }
 
 - (BOOL)openExternalURL:(const GURL&)url linkClicked:(BOOL)linkClicked {
   if (!externalAppLauncher_.get())
     externalAppLauncher_.reset([[ExternalAppLauncher alloc] init]);
 
@@ skipping 29 matching lines @@
 
     if (!finalURL.is_valid()) {
       return NO;
     }
   }
 
   if ([externalAppLauncher_ openURL:finalURL linkClicked:linkClicked]) {
     // Clears pending navigation history after successfully launching the
     // external app.
     DCHECK([self navigationManager]);
-    [[self navigationManager]->GetSessionController() discardNonCommittedItems];
+    [self navigationManager]->DiscardNonCommittedItems();
     // Ensure the UI reflects the current entry, not the just-discarded pending
     // entry.
     [parentTabModel_ notifyTabChanged:self];
     return YES;
   }
   return NO;
 }
 
 - (void)webWillFinishHistoryNavigationFromEntry:(CRWSessionEntry*)fromEntry {
   [parentTabModel_ notifyTabChanged:self];
@@ skipping 205 matching lines @@
 
   // TODO(crbug.com/228171): A hack in session_controller -addPendingItem
   // discusses making tab responsible for distinguishing history stack
   // navigation from new navigations. Because we want a new navigation here, we
   // use |PAGE_TRANSITION_FORM_SUBMIT|. When session_controller changes, so
   // should this.
   ui::PageTransition transition =
       ui::PageTransitionFromInt(ui::PAGE_TRANSITION_FORM_SUBMIT);
   DCHECK([self navigationManager]);
   CRWSessionController* sessionController =
-      [self navigationManager]->GetSessionController();
+      [self navigationManagerImpl]->GetSessionController();
   web::NavigationItem* lastUserItem = [sessionController lastUserItem];
   if (!lastUserItem)
     return;
 
   // |originalUrl| will be empty if a page was open by DOM.
   GURL reloadURL(lastUserItem->GetOriginalRequestURL());
   if (reloadURL.is_empty()) {
     DCHECK(sessionController.openedByDOM);
     reloadURL = lastUserItem->GetVirtualURL();
   }
@@ skipping 18 matching lines @@
   DCHECK(U2FController_);
   [U2FController_ evaluateU2FResultFromU2FURL:URL webState:self.webState];
 }
 
 #pragma mark - CRWWebDelegate and CRWWebStateObserver protocol methods.
 
 // The web page wants to close its own window.
 - (void)webPageOrderedClose {
   // Only allow a web page to close itself if it was opened by DOM, or if there
   // are no navigation items.
-  DCHECK([[self navigationManager]->GetSessionController() isOpenedByDOM] ||
+  DCHECK([[self navigationManagerImpl]->GetSessionController() isOpenedByDOM] ||
          ![self navigationManager]->GetItemCount());
   [self closeThisTab];
 }
 
 // This method is invoked whenever the system believes the URL is about to
 // change, or immediately after any unexpected change of the URL. The apparent
 // destination URL is included in the |url| parameter.
 // Warning: because of the present design it is possible for malicious websites
 // to invoke superflous instances of this delegate with artibrary URLs.
 // Ensure there is nothing here that could be a risk to the user beyond mild
@@ skipping 214 matching lines @@
     return YES;
   }
 
   // Auto-open didn't work. Reset the auto-open flag.
   [metadata unsetShouldAutoOpenLinks];
   return NO;
 }
 
 - (double)lastVisitedTimestamp {
   DCHECK([self navigationManager]);
-  return
-      [[self navigationManager]->GetSessionController() lastVisitedTimestamp];
+  return [[self navigationManagerImpl]->GetSessionController()
+              lastVisitedTimestamp];
 }
 
 - (void)updateLastVisitedTimestamp {
   // Stores this information in self.history and it will be written into disc
   // with other information when needed.
   DCHECK([self navigationManager]);
-  [[self navigationManager]->GetSessionController()
+  [[self navigationManagerImpl]->GetSessionController()
       setLastVisitedTimestamp:[[NSDate date] timeIntervalSince1970]];
 }
 
 - (infobars::InfoBarManager*)infoBarManager {
   DCHECK(self.webState);
   return InfoBarManagerImpl::FromWebState(self.webState);
 }
 
 - (NSArray*)snapshotOverlays {
   return [snapshotOverlayProvider_ snapshotOverlaysForTab:self];
@@ skipping 335 matching lines @@
 
 - (TabModel*)parentTabModel {
   return parentTabModel_;
 }
 
 - (FormInputAccessoryViewController*)inputAccessoryViewController {
   return inputAccessoryViewController_.get();
 }
 
 @end