Remove about:srcdoc url conversion.

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 4803 matching lines @@
   if (SiteIsolationPolicy::UseSubframeNavigationEntries()) {
     params.method = request.httpMethod().latin1();
     if (params.method == "POST")
       params.post_id = post_id;
   }
 
   params.frame_unique_name = item.target().utf8();
   params.item_sequence_number = item.itemSequenceNumber();
   params.document_sequence_number = item.documentSequenceNumber();
 
-  params.is_srcdoc = params.url == content::kAboutSrcDocURL;
-
   // If the page contained a client redirect (meta refresh, document.loc...),
   // set the referrer appropriately.
   if (ds->isClientRedirect()) {
     params.referrer =
         Referrer(params.redirects[0], ds->request().referrerPolicy());
   } else {
     params.referrer =
         RenderViewImpl::GetReferrerFromRequest(frame, ds->request());
   }
 
@@ skipping 1801 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