Added NavigationContext::IsPost.

ios/web/web_state/ui/crw_web_controller.mm

 // Copyright 2012 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/ui/crw_web_controller.h"
 
 #import <WebKit/WebKit.h>
 
 #import <objc/runtime.h>
 #include <stddef.h>
@@ skipping 1523 matching lines @@
       web::NavigationContextImpl::CreateNavigationContext(
           _webStateImpl, requestURL, transition);
 
   web::NavigationItem* item = self.navigationManagerImpl->GetPendingItem();
   // TODO(crbug.com/676129): AddPendingItem does not always create a pending
   // item. Remove this workaround once the bug is fixed.
   if (!item) {
     item = self.navigationManagerImpl->GetLastCommittedItem();
   }
   context->SetNavigationItemUniqueID(item->GetUniqueID());
+  context->SetIsPost([self isCurrentNavigationItemPOST]);
   _webStateImpl->SetIsLoading(true);
   _webStateImpl->OnNavigationStarted(context.get());
   return context;
 }
 
 - (void)updateHTML5HistoryState {
   web::NavigationItemImpl* currentItem = self.currentNavItem;
   if (!currentItem)
     return;
 
@@ skipping 3683 matching lines @@
 - (NSUInteger)observerCount {
   DCHECK_EQ(_observerBridges.size(), [_observers count]);
   return [_observers count];
 }
 
 - (NSString*)referrerFromNavigationAction:(WKNavigationAction*)action {
   return [action.request valueForHTTPHeaderField:kReferrerHeaderName];
 }
 
 @end