Removed XCallbackParameters and related code.

ios/chrome/app/chrome_app_startup_parameters.h

 // Copyright 2015 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_APP_CHROME_APP_STARTUP_PARAMETERS_H_
 #define IOS_CHROME_APP_CHROME_APP_STARTUP_PARAMETERS_H_
 
 #import <UIKit/UIKit.h>
 
 #import "ios/chrome/browser/app_startup_parameters.h"
@@ skipping 12 matching lines @@
   CALLER_APP_APPLE_OTHER,
   CALLER_APP_GOOGLE_YOUTUBE,
   CALLER_APP_GOOGLE_MAPS,
   CALLER_APP_NOT_AVAILABLE,  // Includes being launched from Smart App Banner.
   CALLER_APP_GOOGLE_CHROME_TODAY_EXTENSION,
   MOBILE_SESSION_CALLER_APP_COUNT,
 };
 
 @interface ChromeAppStartupParameters : AppStartupParameters
 
-- (instancetype)initWithExternalURL:(const GURL&)externalURL
-                xCallbackParameters:(XCallbackParameters*)xCallbackParameters
-    NS_UNAVAILABLE;
+- (instancetype)initWithExternalURL:(const GURL&)externalURL NS_UNAVAILABLE;
 
 - (instancetype)initWithExternalURL:(const GURL&)externalURL
-                xCallbackParameters:(XCallbackParameters*)xCallbackParameters
                   declaredSourceApp:(NSString*)declaredSourceApp
                     secureSourceApp:(NSString*)secureSourceApp
                         completeURL:(NSURL*)completeURL
     NS_DESIGNATED_INITIALIZER;
 
 // Returns a ChromeAppStartupParameters instance containing the URL to
 // open (|externalURL|). In case the URL is conforming to the x-callback-url
 // specification, additional information are stored in the returned value.
 //
 // The forms of the URLs we expect are:
@@ skipping 52 matching lines @@
 
 + (instancetype)newAppStartupParametersForCommand:(NSString*)command
                                     withParameter:(id)parameter
                                           withURL:(NSURL*)url
                             fromSourceApplication:(NSString*)appId
                       fromSecureSourceApplication:(NSString*)secureSourceApp;
 
 @end
 
 #endif  // IOS_CHROME_APP_CHROME_APP_STARTUP_PARAMETERS_H_