Disable Feature-Policy HTTP Header

third_party/WebKit/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 1092 matching lines @@
   // will use stale values from HTMLParserOption.
   if (reason == InstallNewDocumentReason::kNavigation)
     DidCommitNavigation();
 
   writer_ =
       DocumentWriter::Create(document, parsing_policy, mime_type, encoding);
 
   // FeaturePolicy is reset in the browser process on commit, so this needs to
   // be initialized and replicated to the browser process after commit messages
   // are sent in didCommitNavigation().
+  // Feature-Policy header is currently disabled while the details of the policy
+  // syntax are being worked out. Unless the Feature Policy experimental
+  // features flag is enabled, then ignore any header received.
+  // TODO(iclelland): Re-enable once the syntax is finalized. (crbug.com/737643)
   document->SetFeaturePolicy(
-      response_.HttpHeaderField(HTTPNames::Feature_Policy));
+      RuntimeEnabledFeatures::FeaturePolicyExperimentalFeaturesEnabled()
+          ? response_.HttpHeaderField(HTTPNames::Feature_Policy)
+          : g_empty_string);
 
   GetFrameLoader().DispatchDidClearDocumentOfWindowObject();
 }
 
 const AtomicString& DocumentLoader::MimeType() const {
   if (writer_)
     return writer_->MimeType();
   return response_.MimeType();
 }
 
 // This is only called by
 // FrameLoader::replaceDocumentWhileExecutingJavaScriptURL()
 void DocumentLoader::ReplaceDocumentWhileExecutingJavaScriptURL(
     const DocumentInit& init,
     const String& source) {
   InstallNewDocument(init, MimeType(),
                      writer_ ? writer_->Encoding() : g_empty_atom,
                      InstallNewDocumentReason::kJavascriptURL,
                      kForceSynchronousParsing, KURL());
   if (!source.IsNull())
     writer_->AppendReplacingData(source);
   EndWriting();
 }
 
 DEFINE_WEAK_IDENTIFIER_MAP(DocumentLoader);
 
 }  // namespace blink