Revert "Make a ResourceThrottle for extensions on top of net::URLRequestThrottlerManager."

Reason for revert:
Conditional jump on uninitialied value was reported on memory bot. See crbug.com/500769
for log.

>    Make a ResourceThrottle for extensions on top of net::URLRequestThrottlerManager.
>
>    net::URLRequestThrottlerManager is used for throttling extensions originated
>    requests. We would like to move it out of net/ and place it in a more appropriate
>    directory. Since content::ResourceThrottle is the standard way to throttle
>    requests, this CL makes URLRequestThrottlerManager into a extensions
>    ResourceThrottle and place it in extensions/browser/. Followup CLs will clean up
>    URLRequestThrottlerManager usage from net/.
>
>    BUG=484241
>
>    Review URL: https://codereview.chromium.org/1171983003
>
>    Cr-Commit-Position: refs/heads/master@{#334457}

BUG=484241, 500769
TBR=xunjieli@chromium.org

Initialize num_flush_callbacks_

BUG=500764
TBR=bubbe@chromium.org

Review URL: https://codereview.chromium.org/1191543004

Cr-Commit-Position: refs/heads/master@{#334544}

1 files changed, 0 insertions, 168 deletions

diff --git a/extensions/browser/extension_throttle_entry.h b/extensions/browser/extension_throttle_entry.h
deleted file mode 100644
index d0f25cb..0000000
--- a/extensions/browser/extension_throttle_entry.h
+++ /dev/null
@@ -1,168 +0,0 @@
-// Copyright (c) 2012 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 EXTENSIONS_BROWSER_EXTENSION_THROTTLE_ENTRY_H_
-#define EXTENSIONS_BROWSER_EXTENSION_THROTTLE_ENTRY_H_
-
-#include <queue>
-#include <string>
-
-#include "base/basictypes.h"
-#include "base/time/time.h"
-#include "extensions/browser/extension_throttle_entry_interface.h"
-#include "net/base/backoff_entry.h"
-#include "net/log/net_log.h"
-
-namespace extensions {
-
-class ExtensionThrottleManager;
-
-// ExtensionThrottleEntry represents an entry of ExtensionThrottleManager.
-// It analyzes requests of a specific URL over some period of time, in order to
-// deduce the back-off time for every request.
-// The back-off algorithm consists of two parts. Firstly, exponential back-off
-// is used when receiving 5XX server errors or malformed response bodies.
-// The exponential back-off rule is enforced by URLRequestHttpJob. Any
-// request sent during the back-off period will be cancelled.
-// Secondly, a sliding window is used to count recent requests to a given
-// destination and provide guidance (to the application level only) on whether
-// too many requests have been sent and when a good time to send the next one
-// would be. This is never used to deny requests at the network level.
-class ExtensionThrottleEntry : public ExtensionThrottleEntryInterface {
- public:
-  // Sliding window period.
-  static const int kDefaultSlidingWindowPeriodMs;
-
-  // Maximum number of requests allowed in sliding window period.
-  static const int kDefaultMaxSendThreshold;
-
-  // Number of initial errors to ignore before starting exponential back-off.
-  static const int kDefaultNumErrorsToIgnore;
-
-  // Initial delay for exponential back-off.
-  static const int kDefaultInitialDelayMs;
-
-  // Factor by which the waiting time will be multiplied.
-  static const double kDefaultMultiplyFactor;
-
-  // Fuzzing percentage. ex: 10% will spread requests randomly
-  // between 90%-100% of the calculated time.
-  static const double kDefaultJitterFactor;
-
-  // Maximum amount of time we are willing to delay our request.
-  static const int kDefaultMaximumBackoffMs;
-
-  // Time after which the entry is considered outdated.
-  static const int kDefaultEntryLifetimeMs;
-
-  // The manager object's lifetime must enclose the lifetime of this object.
-  ExtensionThrottleEntry(ExtensionThrottleManager* manager,
-                         const std::string& url_id);
-
-  // Same as above, but exposes the option to ignore
-  // net::LOAD_MAYBE_USER_GESTURE flag of the request.
-  ExtensionThrottleEntry(ExtensionThrottleManager* manager,
-                         const std::string& url_id,
-                         bool ignore_user_gesture_load_flag_for_tests);
-
-  // The life span of instances created with this constructor is set to
-  // infinite, and the number of initial errors to ignore is set to 0.
-  // It is only used by unit tests.
-  ExtensionThrottleEntry(ExtensionThrottleManager* manager,
-                         const std::string& url_id,
-                         int sliding_window_period_ms,
-                         int max_send_threshold,
-                         int initial_backoff_ms,
-                         double multiply_factor,
-                         double jitter_factor,
-                         int maximum_backoff_ms);
-
-  // Used by the manager, returns true if the entry needs to be garbage
-  // collected.
-  bool IsEntryOutdated() const;
-
-  // Causes this entry to never reject requests due to back-off.
-  void DisableBackoffThrottling();
-
-  // Causes this entry to NULL its manager pointer.
-  void DetachManager();
-
-  // Implementation of ExtensionThrottleEntryInterface.
-  bool ShouldRejectRequest(const net::URLRequest& request) const override;
-  int64 ReserveSendingTimeForNextRequest(
-      const base::TimeTicks& earliest_time) override;
-  base::TimeTicks GetExponentialBackoffReleaseTime() const override;
-  void UpdateWithResponse(int status_code) override;
-  void ReceivedContentWasMalformed(int response_code) override;
-  const std::string& GetURLIdForDebugging() const override;
-
- protected:
-  ~ExtensionThrottleEntry() override;
-
-  void Initialize();
-
-  // Returns true if the given response code is considered a success for
-  // throttling purposes.
-  bool IsConsideredSuccess(int response_code);
-
-  // Equivalent to TimeTicks::Now(), virtual to be mockable for testing purpose.
-  virtual base::TimeTicks ImplGetTimeNow() const;
-
-  // Retrieves the back-off entry object we're using. Used to enable a
-  // unit testing seam for dependency injection in tests.
-  virtual const net::BackoffEntry* GetBackoffEntry() const;
-  virtual net::BackoffEntry* GetBackoffEntry();
-
-  // Returns true if |load_flags| contains a flag that indicates an
-  // explicit request by the user to load the resource. We never
-  // throttle requests with such load flags.
-  static bool ExplicitUserRequest(const int load_flags);
-
-  // Used by tests.
-  base::TimeTicks sliding_window_release_time() const {
-    return sliding_window_release_time_;
-  }
-
-  // Used by tests.
-  void set_sliding_window_release_time(const base::TimeTicks& release_time) {
-    sliding_window_release_time_ = release_time;
-  }
-
-  // Valid and immutable after construction time.
-  net::BackoffEntry::Policy backoff_policy_;
-
- private:
-  // Timestamp calculated by the sliding window algorithm for when we advise
-  // clients the next request should be made, at the earliest. Advisory only,
-  // not used to deny requests.
-  base::TimeTicks sliding_window_release_time_;
-
-  // A list of the recent send events. We use them to decide whether there are
-  // too many requests sent in sliding window.
-  std::queue<base::TimeTicks> send_log_;
-
-  const base::TimeDelta sliding_window_period_;
-  const int max_send_threshold_;
-
-  // True if DisableBackoffThrottling() has been called on this object.
-  bool is_backoff_disabled_;
-
-  // Access it through GetBackoffEntry() to allow a unit test seam.
-  net::BackoffEntry backoff_entry_;
-
-  // Weak back-reference to the manager object managing us.
-  ExtensionThrottleManager* manager_;
-
-  // Canonicalized URL string that this entry is for; used for logging only.
-  std::string url_id_;
-
-  net::BoundNetLog net_log_;
-  bool ignore_user_gesture_load_flag_for_tests_;
-
-  DISALLOW_COPY_AND_ASSIGN(ExtensionThrottleEntry);
-};
-
-}  // namespace extensions
-
-#endif  // EXTENSIONS_BROWSER_EXTENSION_THROTTLE_ENTRY_H_