Use SameDocument instead of SamePage term on iOS.

ios/web/web_state/web_state_impl.h

 // Copyright 2013 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_WEB_STATE_WEB_STATE_IMPL_H_
 #define IOS_WEB_WEB_STATE_WEB_STATE_IMPL_H_
 
 #include <stddef.h>
 #include <stdint.h>
 
@@ skipping 65 matching lines @@
   WebStateFacadeDelegate* GetFacadeDelegate() const;
   void SetFacadeDelegate(WebStateFacadeDelegate* facade_delegate);
 
   // Notifies the observers that a provisional navigation has started.
   void OnProvisionalNavigationStarted(const GURL& url);
 
   // Called when a navigation is committed.
   void OnNavigationCommitted(const GURL& url);
 
   // Notifies the observers that same page navigation did finish.
-  void OnSamePageNavigation(const GURL& url);
+  void OnSameDocumentNavigation(const GURL& url);
 
   // Notifies the observers that navigation to error page did finish.
   void OnErrorPageNavigation(const GURL& url);
 
   // Called when page title was changed.
   void OnTitleChanged();
 
   // Called when the visible security state of the page changes.
   void OnVisibleSecurityStateChange();
 
@@ skipping 274 matching lines @@
 
   // Mojo interface registry for this WebState.
   std::unique_ptr<service_manager::InterfaceRegistry> mojo_interface_registry_;
 
   DISALLOW_COPY_AND_ASSIGN(WebStateImpl);
 };
 
 }  // namespace web
 
 #endif  // IOS_WEB_WEB_STATE_WEB_STATE_IMPL_H_