(Re-)introduce AncestorThrottle to handle 'X-Frame-Options'.

content/renderer/render_frame_impl.cc

 // 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.
 
 #include "content/renderer/render_frame_impl.h"
 
 #include <map>
 #include <string>
 #include <utility>
 #include <vector>
@@ skipping 2354 matching lines @@
   std::string error_html;
   GetContentClient()->renderer()->GetNavigationErrorStrings(
       this, failed_request, error, &error_html, nullptr);
 
   blink::WebFrameLoadType frame_load_type =
       entry ? blink::WebFrameLoadType::BackForward
             : blink::WebFrameLoadType::Standard;
   const blink::WebHistoryItem& history_item =
       entry ? entry->root() : blink::WebHistoryItem();
 
+  // Requests blocked by the X-Frame-Options HTTP response header don't display
+  // error pages but a blank page instead.
+  // TODO(alexmos, mkwst, arthursonzogni): This block can be removed once error
+  // pages are refactored. See crbug.com/588314 and crbug.com/622385.
+  if (error.reason == net::ERR_BLOCKED_BY_RESPONSE) {
+    frame_->loadData("", WebString::fromUTF8("text/html"),
+                     WebString::fromUTF8("UTF-8"), GURL("data:,"), WebURL(),
+                     replace, frame_load_type, history_item,
+                     blink::WebHistoryDifferentDocumentLoad, false);
+    return;
+  }
+
   frame_->loadData(error_html, WebString::fromUTF8("text/html"),
                    WebString::fromUTF8("UTF-8"), GURL(kUnreachableWebDataURL),
                    error.unreachableURL, replace, frame_load_type, history_item,
                    blink::WebHistoryDifferentDocumentLoad, false);
 }
 
 void RenderFrameImpl::DidMeaningfulLayout(
     blink::WebMeaningfulLayout layout_type) {
   for (auto& observer : observers_)
     observer.DidMeaningfulLayout(layout_type);
@@ skipping 4307 matching lines @@
   // event target. Potentially a Pepper plugin will receive the event.
   // In order to tell whether a plugin gets the last mouse event and which it
   // is, we set |pepper_last_mouse_event_target_| to null here. If a plugin gets
   // the event, it will notify us via DidReceiveMouseEvent() and set itself as
   // |pepper_last_mouse_event_target_|.
   pepper_last_mouse_event_target_ = nullptr;
 #endif
 }
 
 }  // namespace content