Replace frame-src with child-src in WebUI CSP

chrome/browser/search/local_ntp_source.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 "chrome/browser/search/local_ntp_source.h"
 
 #include <stddef.h>
 
 #include <memory>
 
@@ skipping 252 matching lines @@
     std::string filename;
     webui::ParsePathAndScale(request->url(), &filename, NULL);
     for (size_t i = 0; i < arraysize(kResources); ++i) {
       if (filename == kResources[i].filename)
         return true;
     }
   }
   return false;
 }
 
-std::string LocalNtpSource::GetContentSecurityPolicyFrameSrc() const {
+std::string LocalNtpSource::GetContentSecurityPolicyChildSrc() const {
   // Allow embedding of most visited iframes.
-  return base::StringPrintf("frame-src %s;",
+  return base::StringPrintf("child-src %s;",
                             chrome::kChromeSearchMostVisitedUrl);
 }