Implement transfer navigation with mojo

content/browser/loader/mojo_async_resource_handler.cc

 // Copyright 2016 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.
 
 #include "content/browser/loader/mojo_async_resource_handler.h"
 
 #include <utility>
 
 #include "base/command_line.h"
 #include "base/containers/hash_tables.h"
@@ skipping 93 matching lines @@
 };
 
 MojoAsyncResourceHandler::MojoAsyncResourceHandler(
     net::URLRequest* request,
     ResourceDispatcherHostImpl* rdh,
     mojom::URLLoaderAssociatedRequest mojo_request,
     mojom::URLLoaderClientAssociatedPtr url_loader_client)
     : ResourceHandler(request),
       rdh_(rdh),
       binding_(this, std::move(mojo_request)),
-      url_loader_client_(std::move(url_loader_client)) {
+      url_loader_client_(std::move(url_loader_client)),
+      weak_factory_(this) {
   DCHECK(url_loader_client_);
   InitializeResourceBufferConstants();
   // This unretained pointer is safe, because |binding_| is owned by |this| and
   // the callback will never be called after |this| is destroyed.
   binding_.set_connection_error_handler(
       base::Bind(&MojoAsyncResourceHandler::Cancel, base::Unretained(this)));
 }
 
 MojoAsyncResourceHandler::~MojoAsyncResourceHandler() {
   if (has_checked_for_sufficient_resources_)
     rdh_->FinishedWithResourcesForRequest(request());
 }
 
+MojoAsyncResourceHandler::TransferCallback
+MojoAsyncResourceHandler::GetTransferCallback() {
+  return base::Bind(&MojoAsyncResourceHandler::OnTransfer,
+                    weak_factory_.GetWeakPtr());
+}
+
 bool MojoAsyncResourceHandler::OnRequestRedirected(
     const net::RedirectInfo& redirect_info,
     ResourceResponse* response,
     bool* defer) {
   // Unlike OnResponseStarted, OnRequestRedirected will NOT be preceded by
   // OnWillRead.
   DCHECK(!shared_writer_);
 
   *defer = true;
   request()->LogBlockedBy("MojoAsyncResourceHandler");
@@ skipping 293 matching lines @@
 void MojoAsyncResourceHandler::Cancel() {
   const ResourceRequestInfoImpl* info = GetRequestInfo();
   ResourceDispatcherHostImpl::Get()->CancelRequestFromRenderer(
       GlobalRequestID(info->GetChildID(), info->GetRequestID()));
 }
 
 void MojoAsyncResourceHandler::ReportBadMessage(const std::string& error) {
   mojo::ReportBadMessage(error);
 }
 
+void MojoAsyncResourceHandler::OnTransfer(
+    mojom::URLLoaderAssociatedRequest mojo_request,
+    mojom::URLLoaderClientAssociatedPtr url_loader_client) {
+  if (!url_loader_client) {
+    // Resumes the request without transferring it to a new process.
+    return;
+  }
+
+  binding_.Unbind();
+  binding_.Bind(std::move(mojo_request));
+  binding_.set_connection_error_handler(
+      base::Bind(&MojoAsyncResourceHandler::Cancel, base::Unretained(this)));
+  url_loader_client_ = std::move(url_loader_client);
+}
+
 }  // namespace content