PlzNavigate: Add first version of NavigationURLLoader.

content/browser/loader/navigation_resource_handler.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_LOADER_NAVIGATION_RESOURCE_HANDLER_H_
+#define CONTENT_BROWSER_LOADER_NAVIGATION_RESOURCE_HANDLER_H_
+
+#include "base/macros.h"
+#include "content/browser/loader/resource_handler.h"
+#include "content/browser/loader/stream_writer.h"
+
+namespace content {
+
+class NavigationURLLoaderImplCore;
+
+// PlzNavigate: The leaf ResourceHandler used with NavigationURLLoaderImplCore.
+class NavigationResourceHandler : public ResourceHandler {
+ public:
+  NavigationResourceHandler(net::URLRequest* request,
+                            NavigationURLLoaderImplCore* core);
+  ~NavigationResourceHandler() override;
+
+  // Called by the loader the cancel the request.
+  void Cancel();
+
+  // Called to the loader to resume a paused redirect.
+  void FollowRedirect();
+
+  // ResourceHandler implementation.
+  void SetController(ResourceController* controller) override;
+  bool OnUploadProgress(uint64 position, uint64 size) override;
+  bool OnRequestRedirected(const net::RedirectInfo& redirect_info,
+                           ResourceResponse* response,
+                           bool* defer) override;
+  bool OnResponseStarted(ResourceResponse* response, bool* defer) override;
+  bool OnWillStart(const GURL& url, bool* defer) override;
+  bool OnBeforeNetworkStart(const GURL& url, bool* defer) override;
+  bool OnWillRead(scoped_refptr<net::IOBuffer>* buf,
+                  int* buf_size,
+                  int min_size) override;
+  bool OnReadCompleted(int bytes_read, bool* defer) override;
+  void OnResponseCompleted(const net::URLRequestStatus& status,
+                           const std::string& security_info,
+                           bool* defer) override;
+  void OnDataDownloaded(int bytes_downloaded) override;
+
+ private:
+  // Clears |core_| and its reference to the resource handler. After calling
+  // this, the lifetime of the request is no longer tied to |core_|.
+  void DetachFromCore();
+
+  NavigationURLLoaderImplCore* core_;
+  StreamWriter writer_;
+
+  DISALLOW_COPY_AND_ASSIGN(NavigationResourceHandler);
+};
+
+}  // namespace content
+
+#endif  // CONTENT_BROWSER_LOADER_CERTIFICATE_RESOURCE_HANDLER_H_