Use SameDocument instead of SamePage term on iOS.

ios/web/web_state/web_state_impl.mm

 // 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.
 
 #import "ios/web/web_state/web_state_impl.h"
 
 #include <stddef.h>
 #include <stdint.h>
 
 #include "base/logging.h"
@@ skipping 169 matching lines @@
   facade_delegate_ = facade_delegate;
 }
 
 void WebStateImpl::OnNavigationCommitted(const GURL& url) {
   std::unique_ptr<NavigationContext> context =
       NavigationContextImpl::CreateNavigationContext(this, url);
   for (auto& observer : observers_)
     observer.DidFinishNavigation(context.get());
 }
 
-void WebStateImpl::OnSamePageNavigation(const GURL& url) {
+void WebStateImpl::OnSameDocumentNavigation(const GURL& url) {
   std::unique_ptr<NavigationContext> context =
-      NavigationContextImpl::CreateSamePageNavigationContext(this, url);
+      NavigationContextImpl::CreateSameDocumentNavigationContext(this, url);
   for (auto& observer : observers_)
     observer.DidFinishNavigation(context.get());
 }
 
 void WebStateImpl::OnErrorPageNavigation(const GURL& url) {
   std::unique_ptr<NavigationContext> context =
       NavigationContextImpl::CreateErrorPageNavigationContext(this, url);
   for (auto& observer : observers_)
     observer.DidFinishNavigation(context.get());
 }
@@ skipping 558 matching lines @@
     const LoadCommittedDetails& load_details) {
   for (auto& observer : observers_)
     observer.NavigationItemCommitted(load_details);
 }
 
 WebState* WebStateImpl::GetWebState() {
   return this;
 }
 
 }  // namespace web