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

ios/clean/chrome/browser/ui/ntp/ntp_consumer.h

Index: ios/clean/chrome/browser/ui/ntp/ntp_consumer.h
diff --git a/ios/clean/chrome/browser/ui/ntp/ntp_consumer.h b/ios/clean/chrome/browser/ui/ntp/ntp_consumer.h
new file mode 100644
index 0000000000000000000000000000000000000000..f54ae11b4e07704213ad2effdf4417c015458e0a
--- /dev/null
+++ b/ios/clean/chrome/browser/ui/ntp/ntp_consumer.h
@@ -0,0 +1,19 @@
+// 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.
+
+#ifndef IOS_CLEAN_CHROME_BROWSER_UI_NTP_NTP_CONSUMER_H_
+#define IOS_CLEAN_CHROME_BROWSER_UI_NTP_NTP_CONSUMER_H_
+
+#import <Foundation/Foundation.h>
+
+@class NewTabPageBarItem;
+
+@protocol NTPConsumer
+
+// Tells NTP what bar items to display.
+- (void)setBarItems:(NSArray<NewTabPageBarItem*>*)items;
+
+@end
+
+#endif  // IOS_CLEAN_CHROME_BROWSER_UI_NTP_NTP_CONSUMER_H_