Cleaned up unused methods from WebStateImpl and NavigationContextImpl.

ios/web/web_state/navigation_context_impl.mm

 // Copyright 2017 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.
 
 #include "ios/web/web_state/navigation_context_impl.h"
 
 #import <Foundation/Foundation.h>
 
 #include "base/memory/ptr_util.h"
 #include "net/http/http_response_headers.h"
 
 namespace web {
 
 // static
 std::unique_ptr<NavigationContextImpl>
 NavigationContextImpl::CreateNavigationContext(WebState* web_state,
                                                const GURL& url) {
   std::unique_ptr<NavigationContextImpl> result(new NavigationContextImpl(
       web_state, url, false /* is_same_document */, false /* is_error_page */,
       nullptr /* response_headers */));
   return result;
 }
 
-// static
-std::unique_ptr<NavigationContextImpl>
-NavigationContextImpl::CreateNavigationContext(
-    WebState* web_state,
-    const GURL& url,
-    const scoped_refptr<net::HttpResponseHeaders>& response_headers) {
-  std::unique_ptr<NavigationContextImpl> resut(
-      new NavigationContextImpl(web_state, url, false /* is_same_document */,
-                                false /* is_error_page */, response_headers));
-  return resut;
-}
-
-// static
-std::unique_ptr<NavigationContextImpl>
-NavigationContextImpl::CreateSameDocumentNavigationContext(WebState* web_state,
-                                                           const GURL& url) {
-  std::unique_ptr<NavigationContextImpl> result(new NavigationContextImpl(
-      web_state, url, true /* is_same_document */, false /* is_error_page */,
-      nullptr /* response_headers */));
-  return result;
-}
-
-// static
-std::unique_ptr<NavigationContextImpl>
-NavigationContextImpl::CreateErrorPageNavigationContext(
-    WebState* web_state,
-    const GURL& url,
-    const scoped_refptr<net::HttpResponseHeaders>& response_headers) {
-  std::unique_ptr<NavigationContextImpl> result(
-      new NavigationContextImpl(web_state, url, false /* is_same_document */,
-                                true /* is_error_page */, response_headers));
-  return result;
-}
-
 #ifndef NDEBUG
 NSString* NavigationContextImpl::GetDescription() const {
   return [NSString stringWithFormat:@"web::WebState: %ld, url: %s, "
                                      "is_same_document: %@, is_error_page_: %@",
                                     reinterpret_cast<long>(web_state_),
                                     url_.spec().c_str(),
                                     is_same_document_ ? @"true" : @"false",
                                     is_error_page_ ? @"true" : @"false"];
 }
 #endif  // NDEBUG
@@ skipping 39 matching lines @@
     const scoped_refptr<net::HttpResponseHeaders>& response_headers)
     : web_state_(web_state),
       url_(url),
       is_same_document_(is_same_document),
       is_error_page_(is_error_page),
       response_headers_(response_headers) {}
 
 NavigationContextImpl::~NavigationContextImpl() = default;
 
 }  // namespace web