Reland "Fix form resubmissions happening silently."

Source/core/loader/DocumentLoader.cpp

 /*
  * Copyright (C) 2006, 2007, 2008 Apple Inc. All rights reserved.
  * Copyright (C) 2011 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  *
  * 1.  Redistributions of source code must retain the above copyright
  *     notice, this list of conditions and the following disclaimer.
@@ skipping 307 matching lines @@
     // If the document specified an application cache manifest, it violates the author's intent if we store it in the memory cache
     // and deny the appcache the chance to intercept it in the future, so remove from the memory cache.
     if (m_frame) {
         if (m_mainResource && m_frame->document()->hasManifest())
             memoryCache()->remove(m_mainResource.get());
     }
     m_applicationCacheHost->finishedLoadingMainResource();
     clearMainResourceHandle();
 }
 
-bool DocumentLoader::isPostOrRedirectAfterPost(const ResourceRequest& newRequest, const ResourceResponse& redirectResponse)
+bool DocumentLoader::isRedirectAfterPost(const ResourceRequest& newRequest, const ResourceResponse& redirectResponse)
 {
-    if (newRequest.httpMethod() == "POST")
-        return true;
-
     int status = redirectResponse.httpStatusCode();
     if (((status >= 301 && status <= 303) || status == 307)
         && m_originalRequest.httpMethod() == "POST")
         return true;
 
     return false;
 }
 
 void DocumentLoader::handleSubstituteDataLoadNow(DocumentLoaderTimer*)
 {
@@ skipping 85 matching lines @@
     }
 
     // Update cookie policy base URL as URL changes, except for subframes, which use the
     // URL of the main frame which doesn't change when we redirect.
     if (frameLoader()->isLoadingMainFrame())
         newRequest.setFirstPartyForCookies(newRequest.url());
 
     // If we're fielding a redirect in response to a POST, force a load from origin, since
     // this is a common site technique to return to a page viewing some data that the POST
     // just modified.
-    // Also, POST requests always load from origin, but this does not affect subresources.
-    if (newRequest.cachePolicy() == UseProtocolCachePolicy && isPostOrRedirectAfterPost(newRequest, redirectResponse))
+    if (newRequest.cachePolicy() == UseProtocolCachePolicy && isRedirectAfterPost(newRequest, redirectResponse))
         newRequest.setCachePolicy(ReloadIgnoringCacheData);
 
     Frame* parent = m_frame->tree()->parent();
     if (parent) {
         if (!parent->loader()->mixedContentChecker()->canRunInsecureContent(parent->document()->securityOrigin(), newRequest.url())) {
             cancelMainResourceLoad(ResourceError::cancelledError(newRequest.url()));
             return;
         }
     }
 
@@ skipping 500 matching lines @@
 void DocumentLoader::replaceDocument(const String& source, Document* ownerDocument)
 {
     m_frame->loader()->stopAllLoaders();
     m_writer = createWriterFor(m_frame, ownerDocument, m_frame->document()->url(), mimeType(), m_writer ? m_writer->encoding() : "",  m_writer ? m_writer->encodingWasChosenByUser() : false, true);
     if (!source.isNull())
         m_writer->appendReplacingData(source);
     endWriting(m_writer.get());
 }
 
 } // namespace WebCore