Remove stale-while-revalidate from content and chrome

content/browser/loader/async_revalidation_driver.h

-// Copyright 2015 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_ASYNC_REVALIDATION_DRIVER_H_
-#define CONTENT_BROWSER_LOADER_ASYNC_REVALIDATION_DRIVER_H_
-
-#include <memory>
-#include <string>
-
-#include "base/callback.h"
-#include "base/macros.h"
-#include "base/memory/ref_counted.h"
-#include "base/memory/weak_ptr.h"
-#include "base/timer/timer.h"
-#include "content/common/content_export.h"
-#include "content/public/browser/resource_throttle.h"
-#include "net/base/io_buffer.h"
-#include "net/url_request/url_request.h"
-
-namespace content {
-
-// This class is responsible for driving the URLRequest for an async
-// revalidation. It is passed an instance of ResourceThrottle created by
-// content::ResourceScheduler to perform throttling on the request.
-class CONTENT_EXPORT AsyncRevalidationDriver
-    : public net::URLRequest::Delegate,
-      public ResourceThrottle::Delegate {
- public:
-  // |completion_callback| is guaranteed to be called on completion,
-  // regardless of success or failure.
-  AsyncRevalidationDriver(std::unique_ptr<net::URLRequest> request,
-                          std::unique_ptr<ResourceThrottle> throttle,
-                          const base::Closure& completion_callback);
-  ~AsyncRevalidationDriver() override;
-
-  void StartRequest();
-
- private:
-  // This enum is logged as histogram "Net.AsyncRevalidation.Result". Only add
-  // new entries at the end and update histograms.xml to match.
-  enum AsyncRevalidationResult {
-    RESULT_LOADED,
-    RESULT_REVALIDATED,
-    RESULT_NET_ERROR,
-    RESULT_READ_ERROR,
-    RESULT_GOT_REDIRECT,
-    RESULT_AUTH_FAILED,
-    RESULT_RESPONSE_TIMEOUT,
-    RESULT_BODY_TIMEOUT,
-    RESULT_MAX
-  };
-
-  // net::URLRequest::Delegate implementation:
-  void OnReceivedRedirect(net::URLRequest* request,
-                          const net::RedirectInfo& redirect_info,
-                          bool* defer) override;
-  void OnAuthRequired(net::URLRequest* request,
-                      net::AuthChallengeInfo* info) override;
-  void OnResponseStarted(net::URLRequest* request) override;
-  void OnReadCompleted(net::URLRequest* request, int bytes_read) override;
-
-  // ResourceThrottle::Delegate implementation:
-  void Resume() override;
-
-  // For simplicity, this class assumes that ResourceScheduler never cancels
-  // requests, and so these three methods are never called.
-  void Cancel() override;
-  void CancelAndIgnore() override;
-  void CancelWithError(int error_code) override;
-
-  // Internal methods.
-  void StartRequestInternal();
-  void CancelRequestInternal(int error, AsyncRevalidationResult result);
-  void StartReading(bool is_continuation);
-  void ReadMore(int* bytes_read);
-  // Logs the result histogram, then calls and clears |completion_callback_|.
-  void ResponseCompleted(AsyncRevalidationResult result);
-  void OnTimeout(AsyncRevalidationResult result);
-  void RecordDefer();
-
-  bool is_deferred_ = false;
-
-  scoped_refptr<net::IOBuffer> read_buffer_;
-  base::OneShotTimer timer_;
-
-  std::unique_ptr<net::URLRequest> request_;
-  std::unique_ptr<ResourceThrottle> throttle_;
-
-  base::Closure completion_callback_;
-
-  base::WeakPtrFactory<AsyncRevalidationDriver> weak_ptr_factory_;
-
-  DISALLOW_COPY_AND_ASSIGN(AsyncRevalidationDriver);
-};
-
-}  // namespace content
-
-#endif  // CONTENT_BROWSER_LOADER_ASYNC_REVALIDATION_DRIVER_H_