Use mojo for Chrome Loading, Part 1

content/browser/loader/resource_dispatcher_host_impl.h

Index: content/browser/loader/resource_dispatcher_host_impl.h
diff --git a/content/browser/loader/resource_dispatcher_host_impl.h b/content/browser/loader/resource_dispatcher_host_impl.h
index 3d960faa85ad57391bc7d6a6eed2b724bdf6ff52..025965c72ace0ceb41d16b6671df503944cf6503 100644
--- a/content/browser/loader/resource_dispatcher_host_impl.h
+++ b/content/browser/loader/resource_dispatcher_host_impl.h
@@ -33,6 +33,7 @@
 #include "content/browser/loader/resource_scheduler.h"
 #include "content/common/content_export.h"
 #include "content/common/resource_request_body.h"
+#include "content/common/url_loader.mojom.h"
 #include "content/public/browser/child_process_data.h"
 #include "content/public/browser/download_item.h"
 #include "content/public/browser/download_url_parameters.h"
@@ -80,6 +81,8 @@ struct DownloadSaveInfo;
 struct NavigationRequestInfo;
 struct Referrer;
 struct ResourceRequest;
+struct ResourceRequestCompletionStatus;
+struct ResourceResponseHead;
 
 // This class is responsible for notifying the IO thread (specifically, the
 // ResourceDispatcherHostImpl) of frame events. It has an interace for callers
@@ -318,6 +321,24 @@ class CONTENT_EXPORT ResourceDispatcherHostImpl
   // or experiment status. For unit tests only.
   void EnableStaleWhileRevalidateForTesting();
 
+  // These functions are used when loading with mojo.
+  // Stores a URLLoader and a URLLoaderClient in |this| object in order to use
+  // them in the next OnRequestResource call.
+  void SetMojoLoaderAndClientrForNextLoadRequest(
+      std::unique_ptr<mojom::URLLoader> loader,
+      mojom::URLLoaderClientPtr client);
+  // Sends |message| with mojo if it is possible and returns whether the message
+  // is sent.
+  bool SendWithMojoIfPossible(const IPC::Message& message,
+                              ResourceMessageFilter* filter);
+  // Add an uninitiated (i.e., resource loading is not yet started) loader in
+  // order to keep it alive.
+  void AddUninitiatedURLLoader(int child_id,
+                               std::unique_ptr<mojom::URLLoader> loader);
+  // Returns an uninitiated URL loader whose raw pointer equals to |loader|.
+  std::unique_ptr<mojom::URLLoader> TakeUninitiatedURLLoader(
+      mojom::URLLoader* loader);
+
  private:
   friend class LoaderIOThreadNotifier;
   friend class ResourceDispatcherHostTest;
@@ -371,8 +392,11 @@ class CONTENT_EXPORT ResourceDispatcherHostImpl
   void OnRenderFrameDeleted(const GlobalFrameRoutingId& global_routing_id);
 
   // Helper function for regular and download requests.
-  void BeginRequestInternal(std::unique_ptr<net::URLRequest> request,
-                            std::unique_ptr<ResourceHandler> handler);
+  void BeginRequestInternal(
+      std::unique_ptr<net::URLRequest> request,
+      std::unique_ptr<ResourceHandler> handler,
+      std::unique_ptr<mojom::URLLoader> url_loader = nullptr,
+      mojom::URLLoaderClientPtr client = nullptr);
 
   void StartLoading(ResourceRequestInfoImpl* info,
                     std::unique_ptr<ResourceLoader> loader);
@@ -483,7 +507,9 @@ class CONTENT_EXPORT ResourceDispatcherHostImpl
   void BeginRequest(int request_id,
                     const ResourceRequest& request_data,
                     IPC::Message* sync_result,  // only valid for sync
-                    int route_id);              // only valid for async
+                    int route_id,               // only valid for async
+                    std::unique_ptr<mojom::URLLoader> url_loader = nullptr,
+                    mojom::URLLoaderClientPtr client = nullptr);
 
   // Creates a ResourceHandler to be used by BeginRequest() for normal resource
   // loading.
@@ -494,7 +520,8 @@ class CONTENT_EXPORT ResourceDispatcherHostImpl
       int route_id,
       int process_type,
       int child_id,
-      ResourceContext* resource_context);
+      ResourceContext* resource_context,
+      bool using_mojo);
 
   // Wraps |handler| in the standard resource handlers for normal resource
   // loading and navigation requests. This adds MimeTypeResourceHandler and
@@ -515,6 +542,13 @@ class CONTENT_EXPORT ResourceDispatcherHostImpl
                            net::RequestPriority new_priority,
                            int intra_priority_value);
 
+  // These function are used to trap messages about to sent to the renderer
+  // and send them via mojo.
+  void OnReceivedResponseForMojo(int request_id,
+                                 const ResourceResponseHead& head);
+  void OnRequestCompleteForMojo(int request_id,
+                                const ResourceRequestCompletionStatus& status);
+
   // Creates ResourceRequestInfoImpl for a download or page save.
   // |download| should be true if the request is a file download.
   ResourceRequestInfoImpl* CreateRequestInfo(
@@ -663,6 +697,11 @@ class CONTENT_EXPORT ResourceDispatcherHostImpl
   // outlive this ResourceDispatcherHostImpl.
   CertStore* cert_store_for_testing_;
 
+  std::unique_ptr<mojom::URLLoader> mojo_loader_for_next_load_request_;
+  mojom::URLLoaderClientPtr mojo_loader_client_for_next_load_request_;
+  std::map<mojom::URLLoader*, std::pair<int, std::unique_ptr<mojom::URLLoader>>>
+      uninitiated_url_loaders_;
+
   DISALLOW_COPY_AND_ASSIGN(ResourceDispatcherHostImpl);
 };