Intercept iTunes links and open iTunes controller.

ios/chrome/browser/itunes_links/itunes_links_observer.h

+// Copyright 2016 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_ITUNES_LINKS_ITUNES_LINKS_OBSERVER_H_
+#define IOS_CHROME_BROWSER_ITUNES_LINKS_ITUNES_LINKS_OBSERVER_H_
+
+#import <Foundation/Foundation.h>
+
+#import "ios/web/public/web_state/web_state_observer_bridge.h"
+
+namespace web {
+class WebState;
+};
+
+@protocol StoreKitLauncher;
+
+// Instances of this class observe navigation events. If a page concerning a
+// product on the iTunes App Store is loaded, this class will trigger the
+// opening of a SKStoreProductViewController presenting the information of the
+// said product.
+// The goal of this class is to workaround a bug where Apple serves the wrong
+// content for itunes.apple.com pages, see http://crbug.com/623016.
+@interface ITunesLinksObserver : NSObject<CRWWebStateObserver>
+- (instancetype)initWithWebState:(web::WebState*)webState
+    NS_DESIGNATED_INITIALIZER;
+
+- (instancetype)init NS_UNAVAILABLE;
+
+// Sets the object responsible for showing the App Store product page.
+// |storeKitLauncher| can be nil.
+- (void)setStoreKitLauncher:(id<StoreKitLauncher>)storeKitLauncher;
+
+@end
+
+#endif  // IOS_CHROME_BROWSER_ITUNES_LINKS_ITUNES_LINKS_OBSERVER_H_