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

third_party/WebKit/Source/core/loader/FrameLoader.cpp

Index: third_party/WebKit/Source/core/loader/FrameLoader.cpp
diff --git a/third_party/WebKit/Source/core/loader/FrameLoader.cpp b/third_party/WebKit/Source/core/loader/FrameLoader.cpp
index fde5f299ac1e539ba4f62f6f845d6b91866f77a7..13930700ef71a69b652b4b77befa6799b4810a41 100644
--- a/third_party/WebKit/Source/core/loader/FrameLoader.cpp
+++ b/third_party/WebKit/Source/core/loader/FrameLoader.cpp
@@ -221,9 +221,9 @@ void FrameLoader::init() {
   initialRequest.setFrameType(m_frame->isMainFrame()
                                   ? WebURLRequest::FrameTypeTopLevel
                                   : WebURLRequest::FrameTypeNested);
-  m_provisionalDocumentLoader =
-      client()->createDocumentLoader(m_frame, initialRequest, SubstituteData(),
-                                     ClientRedirectPolicy::NotClientRedirect);
+  m_provisionalDocumentLoader = client()->createDocumentLoader(
+      m_frame, initialRequest, SubstituteData(),
+      ClientRedirectPolicy::NotClientRedirect, nullptr);
   m_provisionalDocumentLoader->startLoadingMainResource();
   m_frame->document()->cancelParsing();
   m_stateMachine.advanceTo(
@@ -1689,7 +1689,7 @@ void FrameLoader::startLoad(FrameLoadRequest& frameLoadRequest,
       frameLoadRequest.substituteData().isValid()
           ? frameLoadRequest.substituteData()
           : defaultSubstituteDataForURL(resourceRequest.url()),
-      frameLoadRequest.clientRedirect());
+      frameLoadRequest.clientRedirect(), frameLoadRequest.originDocument());

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

How will this eventually work in a oopif world?

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

We'd still have a DocumentLoader in the original renderer. When we swap from
local to remote, content can read off the requestor URL then...

It's not great, but I can't really think of anything better =/

In my ideal world, content would just track this: whenever we initiate a
navigation, content/browser would take a note of the URL of the requestor frame
at the time. It'd require aggressively copying the (potentially) large URL
though. I'm a bit torn about what the best approach is atm... I think this would
be longer in the long run, but we'd want to figure out a way to defer the URL
copy until actual commit type.

(I'll talk to creis@ and nasko@ more about this today)

   m_provisionalDocumentLoader->setNavigationType(navigationType);
   m_provisionalDocumentLoader->setReplacesCurrentHistoryItem(
       type == FrameLoadTypeReplaceCurrentItem);