Convert main NTP panel to UIViewController.

ios/chrome/browser/ui/ntp/new_tab_page_controller.h

 // 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.
 
 #ifndef IOS_CHROME_BROWSER_UI_NTP_NEW_TAB_PAGE_CONTROLLER_H_
 #define IOS_CHROME_BROWSER_UI_NTP_NEW_TAB_PAGE_CONTROLLER_H_
 
 #import <UIKit/UIKit.h>
 #include <string>
 
@@ skipping 67 matching lines @@
   base::scoped_nsprotocol<id<NewTabPagePanelProtocol>> bookmarkController_;
   base::scoped_nsobject<GoogleLandingController> googleLandingController_;
   base::scoped_nsprotocol<id<NewTabPagePanelProtocol>> incognitoController_;
   // The currently visible controller, one of the above.
   id<NewTabPagePanelProtocol> currentController_;  // weak
 }
 
 @property(nonatomic, assign) id<CRWSwipeRecognizerProvider>
     swipeRecognizerProvider;
 
+// To ease modernizing the NTP only the internal panels are being converted
+// to UIViewControllers.  This means all the plumbing between the
+// BrowserViewController and the internal NTP panels (WebController, NTP)
+// hierarchy is skipped.  While normally the logic to push and pop a view
+// controller would be owned by a coordinator, in this case the old NTP
+// controller adds and removes child view controllers itself when a load
+// is initiated, and when WebController calls -willBeDismissed.
+@property(nonatomic, assign) UIViewController* parentViewController;

[rohitrao (ping after 24h), 2017/04/12 12:45:09]

Blank line after.

[justincohen, 2017/04/12 14:23:12]

Done.

 // Init with the given url (presumably "chrome://newtab") and loader object.
 // |loader| may be nil, but isn't retained so it must outlive this controller.
 // Dominant color cache is passed to bookmark controller only, to optimize
 // favicon processing.
 - (id)initWithUrl:(const GURL&)url
                 loader:(id<UrlLoader>)loader
                focuser:(id<OmniboxFocuser>)focuser
            ntpObserver:(id<NewTabPageControllerObserver>)ntpObserver
           browserState:(ios::ChromeBrowserState*)browserState
             colorCache:(NSMutableDictionary*)colorCache
     webToolbarDelegate:(id<WebToolbarDelegate>)webToolbarDelegate
               tabModel:(TabModel*)tabModel;
 
 // Select a panel based on the given |panelType|.
 - (void)selectPanel:(NewTabPage::PanelIdentifier)panelType;
 
 // Returns |YES| if the current visible controller should show the keyboard
 // shield.
 - (BOOL)wantsKeyboardShield;
 
 // Returns |YES| if the current visible controller allows showing the location
 // bar hint text.
 - (BOOL)wantsLocationBarHintText;
 
 @end
 
 #endif  // IOS_CHROME_BROWSER_UI_NTP_NEW_TAB_PAGE_CONTROLLER_H_