Remove WebToolbarDelegate from GoogleLandingDataSource.

ios/chrome/browser/ui/ntp/google_landing_controller.mm

 // Copyright 2013 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/ui/ntp/google_landing_controller.h"
 
 #include <algorithm>
 
 #include "base/mac/foundation_util.h"
 #include "base/metrics/user_metrics.h"
@@ skipping 175 matching lines @@
 // Gets the icon of a what's new promo.
 // TODO(crbug.com/694750): This should not be WhatsNewIcon.
 @property(nonatomic, assign) WhatsNewIcon promoIcon;
 
 // |YES| if a what's new promo can be displayed.
 @property(nonatomic, assign) BOOL promoCanShow;
 
 // The number of tabs to show in the google landing fake toolbar.
 @property(nonatomic, assign) int tabCount;
 
+// |YES| if the google landing toolbar can show the forward arrow.

[rohitrao (ping after 24h), 2017/04/28 10:39:59]

Perhaps mention somewhere that these two values are cached because they need to
be pushed into the header view, and the header view may not currently exist.

[justincohen, 2017/04/28 13:23:04]

Done.

+@property(nonatomic, assign) BOOL canGoForward;
+
+// |YES| if the google landing toolbar can show the back arrow.
+@property(nonatomic, assign) BOOL canGoBack;
+
 // iPhone landscape uses a slightly different layout for the doodle and search
 // field frame. Returns the proper frame from |frames| based on orientation,
 // centered in the view.
 - (CGRect)getOrientationFrame:(const CGRect[])frames;
 // Returns the proper frame for the doodle.
 - (CGRect)doodleFrame;
 // Returns the proper frame for the search field.
 - (CGRect)searchFieldFrame;
 // Returns the height to use for the What's New promo view.
 - (CGFloat)promoHeaderHeight;
@@ skipping 50 matching lines @@
 @synthesize dataSource = _dataSource;
 // Property declared in NewTabPagePanelProtocol.
 @synthesize delegate = _delegate;
 @synthesize isOffTheRecord = _isOffTheRecord;
 @synthesize logoIsShowing = _logoIsShowing;
 @synthesize promoText = _promoText;
 @synthesize promoIcon = _promoIcon;
 @synthesize promoCanShow = _promoCanShow;
 @synthesize maximumMostVisitedSitesShown = _maximumMostVisitedSitesShown;
 @synthesize tabCount = _tabCount;
+@synthesize canGoForward = _canGoForward;
+@synthesize canGoBack = _canGoBack;
 @synthesize voiceSearchIsEnabled = _voiceSearchIsEnabled;
 
 - (void)loadView {
   self.view = [[[GoogleLandingView alloc]
       initWithFrame:[UIScreen mainScreen].bounds] autorelease];
 }
 
 - (void)viewDidLoad {
   [super viewDidLoad];
   [self.view setAutoresizingMask:UIViewAutoresizingFlexibleHeight |
@@ skipping 717 matching lines @@
                                     forIndexPath:indexPath] retain]);
       [_headerView addSubview:[self.logoVendor view]];
       [_headerView addSubview:_searchTapTarget];
       [_headerView addViewsToSearchField:_searchTapTarget];
 
       if (!IsIPadIdiom()) {
         // iPhone header also contains a toolbar since the normal toolbar is
         // hidden.
         [_headerView addToolbarWithDataSource:self.dataSource];
         [_headerView setToolbarTabCount:self.tabCount];
+        [_headerView setCanGoForward:self.canGoForward];
+        [_headerView setCanGoBack:self.canGoBack];
       }
       [_supplementaryViews addObject:_headerView];
     }
     return _headerView;
   }
 
   if (indexPath.section == SectionWithMostVisited) {
     if (!_promoHeaderView) {
       _promoHeaderView.reset([[collectionView
           dequeueReusableSupplementaryViewOfKind:
@@ skipping 474 matching lines @@
   NSIndexPath* indexPath =
       [NSIndexPath indexPathForRow:index inSection:SectionWithMostVisited];
   [_mostVisitedView reloadItemsAtIndexPaths:@[ indexPath ]];
 }
 
 - (void)setTabCount:(int)tabCount {
   _tabCount = tabCount;
   [_headerView setToolbarTabCount:self.tabCount];
 }
 
+- (void)setCanGoForward:(BOOL)canGoForward {
+  _canGoForward = canGoForward;
+  [_headerView setCanGoForward:self.canGoForward];
+}
+
+- (void)setCanGoBack:(BOOL)canGoBack {
+  _canGoBack = canGoBack;
+  [_headerView setCanGoBack:self.canGoBack];
+}
 @end