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"
+
+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.
+class NavigationRequest {
+ public:
+  explicit NavigationRequest();
+  ~NavigationRequest();
+
+  // Called on the UI thread by the RenderFrameHostManager that owns the
+  // NavigationRequest.
+  void BeginNavigation(const NavigationRequestInfo& info,
+                       scoped_refptr<ResourceRequestBody> body,
+                       int64 frame_node_id);
+
+  DISALLOW_COPY_AND_ASSIGN(NavigationRequest);
+};
+
+}  // namespace content
+
+#endif  // CONTENT_BROWSER_FRAME_HOST_NAVIGATION_REQUEST_H_