Expose the initiating origin/URL of a navigation in the Blink public API

third_party/WebKit/Source/core/loader/DocumentLoader.h

 /*
  * Copyright (C) 2006, 2007, 2008, 2009 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 54 matching lines @@
 
 class CORE_EXPORT DocumentLoader
     : public GarbageCollectedFinalized<DocumentLoader>,
       private RawResourceClient {
   USING_GARBAGE_COLLECTED_MIXIN(DocumentLoader);
 
  public:
   static DocumentLoader* create(LocalFrame* frame,
                                 const ResourceRequest& request,
                                 const SubstituteData& data,
-                                ClientRedirectPolicy clientRedirectPolicy) {
-    return new DocumentLoader(frame, request, data, clientRedirectPolicy);
+                                ClientRedirectPolicy clientRedirectPolicy,
+                                Document* requestorDocument = nullptr) {

[dcheng, 2016/11/23 08:32:59]

The default arg made it easier to add this argument, but I'm happy to make it
explicit (and update the tests) instead.

[Mike West, 2016/11/23 11:11:20]

Looks like we only call it in ~5 places, mostly tests. If you don't mind making
it explicit, I'd prefer that.

[dcheng, 2016/11/23 14:41:44]

Done.

+    return new DocumentLoader(frame, request, data, clientRedirectPolicy,
+                              requestorDocument);
   }
   ~DocumentLoader() override;
 
   LocalFrame* frame() const { return m_frame; }
 
   virtual void detachFromFrame();
 
   unsigned long mainResourceIdentifier() const;
 
   void replaceDocumentWhileExecutingJavaScriptURL(const DocumentInit&,
@@ skipping 94 matching lines @@
                                   LinkLoader::MediaPreloadPolicy);
 
   Resource* startPreload(Resource::Type, FetchRequest&);
 
   DECLARE_VIRTUAL_TRACE();
 
  protected:
   DocumentLoader(LocalFrame*,
                  const ResourceRequest&,
                  const SubstituteData&,
-                 ClientRedirectPolicy);
+                 ClientRedirectPolicy,
+                 Document* requestorDocument);
+
+  Document* requestorDocument() const { return m_requestorDocument; }
 
   void didRedirect(const KURL& oldURL, const KURL& newURL);
 
   Vector<KURL> m_redirectChain;
 
  private:
   static DocumentWriter* createWriterFor(const DocumentInit&,
                                          const AtomicString& mimeType,
                                          const AtomicString& encoding,
                                          bool dispatchWindowObjectAvailable,
@@ skipping 32 matching lines @@
   bool shouldContinueForResponse() const;
 
   Member<LocalFrame> m_frame;
   Member<ResourceFetcher> m_fetcher;
   std::unique_ptr<WebDocumentSubresourceFilter> m_subresourceFilter;
 
   Member<RawResource> m_mainResource;
 
   Member<DocumentWriter> m_writer;
 
+  Member<Document> m_requestorDocument;
+
   // A reference to actual request used to create the data source.
   // The only part of this request that should change is the url, and
   // that only in the case of a same-document navigation.
   ResourceRequest m_originalRequest;
 
   SubstituteData m_substituteData;
 
   // The 'working' request. It may be mutated
   // several times from the original request to include additional
   // headers, cookie information, canonicalization and redirects.
@@ skipping 31 matching lines @@
   // Used to protect against reentrancy into dataReceived().
   bool m_inDataReceived;
   RefPtr<SharedBuffer> m_dataBuffer;
 };
 
 DECLARE_WEAK_IDENTIFIER_MAP(DocumentLoader);
 
 }  // namespace blink
 
 #endif  // DocumentLoader_h