[ios clean] Add placeholder for NTP bookmarks, chrome home and open tabs.

ios/clean/chrome/browser/ui/ntp/ntp_home_mediator.mm

+// Copyright 2017 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/clean/chrome/browser/ui/ntp/ntp_home_mediator.h"
+
+#import "ios/clean/chrome/browser/ui/commands/tab_commands.h"
+#import "ios/web/public/navigation_manager.h"
+#include "ui/base/page_transition_types.h"
+#include "url/gurl.h"
+
+#if !defined(__has_feature) || !__has_feature(objc_arc)
+#error "This file requires ARC support."
+#endif
+
+@interface NTPHomeMediator ()
+@end
+
+@implementation NTPHomeMediator
+@synthesize dispatcher = _dispatcher;
+
+#pragma mark - UrlLoader
+
+- (void)loadURL:(const GURL&)url
+             referrer:(const web::Referrer&)referrer
+           transition:(ui::PageTransition)transition
+    rendererInitiated:(BOOL)rendererInitiated {
+  web::NavigationManager::WebLoadParams params(url);
+  params.transition_type = transition;
+  [self.dispatcher loadURL:params];
+}
+
+- (void)webPageOrderedOpen:(const GURL&)url
+                  referrer:(const web::Referrer&)referrer
+              inBackground:(BOOL)inBackground
+                  appendTo:(OpenPosition)appendTo {
+}
+
+- (void)webPageOrderedOpen:(const GURL&)url
+                  referrer:(const web::Referrer&)referrer
+               inIncognito:(BOOL)inIncognito
+              inBackground:(BOOL)inBackground
+                  appendTo:(OpenPosition)appendTo {
+}
+
+- (void)loadSessionTab:(const sessions::SessionTab*)sessionTab {
+}
+
+- (void)loadJavaScriptFromLocationBar:(NSString*)script {
+}
+
+#pragma mark - OmniboxFocuser
+
+- (void)focusOmnibox {
+}
+
+- (void)cancelOmniboxEdit {
+}
+
+- (void)focusFakebox {
+}
+
+- (void)onFakeboxBlur {
+}
+
+- (void)onFakeboxAnimationComplete {
+}
+
+@end