Add a FrameHostMsg_BeginNavigation IPC

content/browser/frame_host/navigation_request.h

+// Copyright 2014 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_FRAME_HOST_NAVIGATION_REQUEST_H_
+#define CONTENT_BROWSER_FRAME_HOST_NAVIGATION_REQUEST_H_
+
+#include "base/basictypes.h"
+#include "base/memory/ref_counted.h"
+#include "content/browser/frame_host/navigation_request_info.h"
+
+namespace content {
+struct NavigationRequestInfo;
+class ResourceRequestBody;
+
+// A UI thread object that owns a navigation request until it commits. It
+// ensures the UI thread can start a navigation request in the
+// ResourceDispatcherHost (that lives on the IO thread). For a more precise
+// description of the intended interactions between UI and IO thread during
+// navigation, please see the PlzNavigate design doc.

[nasko, 2014/07/07 11:35:07]

While I love the PlzNavigate codename, I'm not sure it is the best thing to use
in comments. Some of the content of that document will have to be described in a
comment somewhere in the codebase, though not sure what the best spot is right
now.

I think the important details concerning this object should be described here.
It will be fine to put a TODO to add those comments later.

[clamy, 2014/07/07 13:36:23]

Done.

+class NavigationRequest {
+ public:
+  explicit NavigationRequest(const NavigationRequestInfo& info,
+                             int64 frame_node_id);
+  ~NavigationRequest();
+
+  NavigationRequestInfo info() const { return info_; }

[nasko, 2014/07/07 11:35:07]

Wouldn't this return a full copy? Is this the intention here? It is also only
used for tests, so it should indicate this using a suffix in the function name.

[clamy, 2014/07/07 13:36:23]

Done.

+  int64 frame_node_id() const { return frame_node_id_; }
+
+  // Called on the UI thread by the RenderFrameHostManager that owns the

[nasko, 2014/07/07 11:35:07]

nit: s/that/which/

[clamy, 2014/07/07 13:36:23]

Done.

+  // NavigationRequest.
+  void BeginNavigation(scoped_refptr<ResourceRequestBody> body);
+
+ private:
+  const NavigationRequestInfo info_;
+  const int64 frame_node_id_;
+
+  DISALLOW_COPY_AND_ASSIGN(NavigationRequest);
+};
+
+}  // namespace content
+
+#endif  // CONTENT_BROWSER_FRAME_HOST_NAVIGATION_REQUEST_H_