Moved NavigationManagerImpl serialization out of CRWSessionController.

ios/web/public/crw_navigation_manager_storage.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_WEB_PUBLIC_CRW_NAVIGATION_MANAGER_STORAGE_H_
+#define IOS_WEB_PUBLIC_CRW_NAVIGATION_MANAGER_STORAGE_H_
+
+#import <Foundation/Foundation.h>
+
+@class CRWSessionCertificatePolicyManager;
+
+// NSCoding-compliant class used to serialize NavigationManager's persisted
+// properties.
+// TODO(crbug.com/685388): Investigate using code from the sessions component.
+@interface CRWNavigationManagerStorage : NSObject<NSCoding>
+
+@property(nonatomic, copy) NSString* tabID;
+@property(nonatomic, copy) NSString* openerID;
+@property(nonatomic, getter=isOpenedByDOM) BOOL openedByDOM;
+@property(nonatomic, assign) NSInteger openerNavigationIndex;
+@property(nonatomic, copy) NSString* windowName;
+@property(nonatomic, assign) NSInteger currentNavigationIndex;
+@property(nonatomic, assign) NSInteger previousNavigationIndex;
+@property(nonatomic, assign) NSTimeInterval lastVisitedTimestamp;
+// TODO(crbug.com/454984): |entries| currently contains CRWSessionEntries.  Once
+// NavigationItemImpls are encoded/decoded using CRWNavigationItemSerializations
+// (analogous to the approach taken with NavigationManager), this will
+// become an array of CRWNavigationItemSerializations.
+@property(nonatomic, copy) NSArray* entries;
+@property(nonatomic, retain)
+    CRWSessionCertificatePolicyManager* sessionCertificatePolicyManager;
+
+@end
+
+#endif  // IOS_WEB_PUBLIC_CRW_NAVIGATION_MANAGER_STORAGE_H_