Implement transfer navigation with mojo

content/browser/loader/resource_request_info_impl.h

 // Copyright (c) 2012 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.
 
 #ifndef CONTENT_BROWSER_LOADER_RESOURCE_REQUEST_INFO_IMPL_H_
 #define CONTENT_BROWSER_LOADER_RESOURCE_REQUEST_INFO_IMPL_H_
 
 #include <memory>
 #include <string>
 
+#include "base/callback.h"
 #include "base/gtest_prod_util.h"
 #include "base/macros.h"
 #include "base/memory/ref_counted.h"
 #include "base/memory/weak_ptr.h"
 #include "base/supports_user_data.h"
 #include "content/browser/service_worker/service_worker_context_wrapper.h"
 #include "content/common/resource_request_body_impl.h"
+#include "content/common/url_loader.mojom.h"
 #include "content/public/browser/navigation_ui_data.h"
 #include "content/public/browser/resource_request_info.h"
 #include "content/public/common/referrer.h"
 #include "content/public/common/resource_type.h"
 #include "net/base/load_states.h"
 
 namespace content {
 class DetachableResourceHandler;
 class ResourceContext;
 class ResourceMessageFilter;
 struct GlobalRequestID;
 struct GlobalRoutingID;
 
 // Holds the data ResourceDispatcherHost associates with each request.
 // Retrieve this data by calling ResourceDispatcherHost::InfoForRequest.
 class ResourceRequestInfoImpl : public ResourceRequestInfo,
                                 public base::SupportsUserData::Data {
  public:
+  using TransferCallback =
+      base::Callback<void(mojom::URLLoaderAssociatedRequest,
+                          mojom::URLLoaderClientAssociatedPtr)>;
+
   // Returns the ResourceRequestInfoImpl associated with the given URLRequest.
   CONTENT_EXPORT static ResourceRequestInfoImpl* ForRequest(
       net::URLRequest* request);
 
   // And, a const version for cases where you only need read access.
   CONTENT_EXPORT static const ResourceRequestInfoImpl* ForRequest(
       const net::URLRequest* request);
 
   CONTENT_EXPORT ResourceRequestInfoImpl(
       int process_type,
@@ skipping 70 matching lines @@
 
   // Updates the data associated with this request after it is is transferred
   // to a new renderer process.  Not all data will change during a transfer.
   // We do not expect the ResourceContext to change during navigation, so that
   // does not need to be updated.
   void UpdateForTransfer(int child_id,
                          int route_id,
                          int render_frame_id,
                          int origin_pid,
                          int request_id,
-                         base::WeakPtr<ResourceMessageFilter> filter);
+                         base::WeakPtr<ResourceMessageFilter> filter,
+                         mojom::URLLoaderAssociatedRequest url_loader_request,

[clamy, 2016/11/16 16:38:53]

I don't think ResourceRequestInfo is the right place to do the mojo-related
work, as it's meant to store parameters related to the request and not execute a
lot of logic. I would suggest using content::ResourceLoader instead, if it still
exist in the Mojo world. content::ResourceLoader contains several functions
related to transfers, so I would use this instead.

[yhirano, 2016/11/17 15:23:19]

Thanks. How about having a callback in NavigatorResourceThrottle? ResourceLoader
already has a callback and introducing another one looks a bit confusing to me.

[clamy, 2016/11/21 17:55:54]

Ok after seeing the other patchset, I think the version in ResourceRequestInfo
was better. Can you add more comments about what the callback is used for, and a
DCHECK similar to what I mentioned in NavigationResourceThrottle? Thanks! 

[yhirano, 2016/11/22 08:12:55]

Done. Unfortunately, ResourceRequestInfoImpl doesn't know if mojo-loading is
enabled or not. It is controlled by a runtime flag in the renderer.

+                         mojom::URLLoaderClientAssociatedPtr url_loader_client);
 
   // Whether this request is part of a navigation that should replace the
   // current session history entry. This state is shuffled up and down the stack
   // for request transfers.
   bool should_replace_current_entry() const {
     return should_replace_current_entry_;
   }
 
   // DetachableResourceHandler for this request.  May be NULL.
   DetachableResourceHandler* detachable_handler() const {
@@ skipping 64 matching lines @@
   // the ResourceMessageFilter will be null in this case. All other requests
   // should access the ServiceWorkerContext through the ResourceMessageFilter.
   void set_service_worker_context(
       scoped_refptr<ServiceWorkerContextWrapper> service_worker_context) {
     service_worker_context_ = service_worker_context;
   }
   ServiceWorkerContextWrapper* service_worker_context() const {
     return service_worker_context_.get();
   }
 
+  void set_on_transfer(const TransferCallback& on_transfer) {
+    on_transfer_ = on_transfer;
+  }
+
  private:
   FRIEND_TEST_ALL_PREFIXES(ResourceDispatcherHostTest,
                            DeletedFilterDetached);
   FRIEND_TEST_ALL_PREFIXES(ResourceDispatcherHostTest,
                            DeletedFilterDetachedRedirect);
   // Non-owning, may be NULL.
   DetachableResourceHandler* detachable_handler_;
 
   int process_type_;
   int child_id_;
@@ skipping 24 matching lines @@
   // exits during a transfer.
   base::WeakPtr<ResourceMessageFilter> filter_;
   bool report_raw_headers_;
   bool is_async_;
   bool is_using_lofi_;
   const std::string original_headers_;
   scoped_refptr<ResourceRequestBodyImpl> body_;
   bool initiated_in_secure_context_;
   std::unique_ptr<NavigationUIData> navigation_ui_data_;
   scoped_refptr<ServiceWorkerContextWrapper> service_worker_context_;
+  TransferCallback on_transfer_;
 
   DISALLOW_COPY_AND_ASSIGN(ResourceRequestInfoImpl);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_LOADER_RESOURCE_REQUEST_INFO_IMPL_H_