Preserving Content-Type header from http request in OpenURL path.

content/browser/frame_host/navigator.h

Index: content/browser/frame_host/navigator.h
diff --git a/content/browser/frame_host/navigator.h b/content/browser/frame_host/navigator.h
index 1580753ec3ed0ed39d8bb14017c215f9625e6d24..2f1a5906639c045e8e6fe5ee48072dc5ece1a2c0 100644
--- a/content/browser/frame_host/navigator.h
+++ b/content/browser/frame_host/navigator.h
@@ -114,6 +114,7 @@ class CONTENT_EXPORT Navigator : public base::RefCounted<Navigator> {
       const GURL& url,
       bool uses_post,
       const scoped_refptr<ResourceRequestBodyImpl>& body,
+      const std::string& extra_headers,
       SiteInstance* source_site_instance,
       const Referrer& referrer,
       WindowOpenDisposition disposition,
@@ -134,7 +135,8 @@ class CONTENT_EXPORT Navigator : public base::RefCounted<Navigator> {
       const GlobalRequestID& transferred_global_request_id,
       bool should_replace_current_entry,
       const std::string& method,
-      scoped_refptr<ResourceRequestBodyImpl> post_body) {}
+      scoped_refptr<ResourceRequestBodyImpl> post_body,
+      const std::string& extra_headers) {}

[Charlie Reis, 2016/09/30 21:31:55]

Is this only for the RenderFrameProxyHost case?  Maybe we should document that
if so, since we don't appear to be passing anything during a real transfer
(which happens after the request has been made).

(I suppose this depends on the other discussion in
RenderFrameHostManager::OnCrossSiteResponse.)

[Łukasz Anforowicz, 2016/09/30 23:17:00]

Good point.  I haven't considered this angle.  FWIW, I've added a TODO comment
in RenderFrameProxyHost::OnOpenURL, next to the RequestTransferURL call that we
want to replace with RequestOpenURL call in the long-term.

 
   // PlzNavigate
   // Called after receiving a BeforeUnloadACK IPC from the renderer. If