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diff --git a/chromium/net/base/backoff_entry.h b/chromium/net/base/backoff_entry.h
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+++ b/chromium/net/base/backoff_entry.h
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+// 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 NET_BASE_BACKOFF_ENTRY_H_
+#define NET_BASE_BACKOFF_ENTRY_H_
+
+#include "base/threading/non_thread_safe.h"
+#include "base/time/time.h"
+#include "net/base/net_export.h"
+
+namespace net {
+
+// Provides the core logic needed for randomized exponential back-off
+// on requests to a given resource, given a back-off policy.
+//
+// This utility class knows nothing about network specifics; it is
+// intended for reuse in various networking scenarios.
+class NET_EXPORT BackoffEntry : NON_EXPORTED_BASE(public base::NonThreadSafe) {
+ public:
+  // The set of parameters that define a back-off policy.
+  struct Policy {
+    // Number of initial errors (in sequence) to ignore before applying
+    // exponential back-off rules.
+    int num_errors_to_ignore;
+
+    // Initial delay.  The interpretation of this value depends on
+    // always_use_initial_delay.  It's either how long we wait between
+    // requests before backoff starts, or how much we delay the first request
+    // after backoff starts.
+    int initial_delay_ms;
+
+    // Factor by which the waiting time will be multiplied.
+    double multiply_factor;
+
+    // Fuzzing percentage. ex: 10% will spread requests randomly
+    // between 90%-100% of the calculated time.
+    double jitter_factor;
+
+    // Maximum amount of time we are willing to delay our request, -1
+    // for no maximum.
+    int64 maximum_backoff_ms;
+
+    // Time to keep an entry from being discarded even when it
+    // has no significant state, -1 to never discard.
+    int64 entry_lifetime_ms;
+
+    // If true, we always use a delay of initial_delay_ms, even before
+    // we've seen num_errors_to_ignore errors.  Otherwise, initial_delay_ms
+    // is the first delay once we start exponential backoff.
+    //
+    // So if we're ignoring 1 error, we'll see (N, N, Nm, Nm^2, ...) if true,
+    // and (0, 0, N, Nm, ...) when false, where N is initial_backoff_ms and
+    // m is multiply_factor, assuming we've already seen one success.
+    bool always_use_initial_delay;
+  };
+
+  // Lifetime of policy must enclose lifetime of BackoffEntry. The
+  // pointer must be valid but is not dereferenced during construction.
+  explicit BackoffEntry(const Policy* const policy);
+  virtual ~BackoffEntry();
+
+  // Inform this item that a request for the network resource it is
+  // tracking was made, and whether it failed or succeeded.
+  void InformOfRequest(bool succeeded);
+
+  // Returns true if a request for the resource this item tracks should
+  // be rejected at the present time due to exponential back-off policy.
+  bool ShouldRejectRequest() const;
+
+  // Returns the absolute time after which this entry (given its present
+  // state) will no longer reject requests.
+  base::TimeTicks GetReleaseTime() const;
+
+  // Returns the time until a request can be sent.
+  base::TimeDelta GetTimeUntilRelease() const;
+
+  // Causes this object reject requests until the specified absolute time.
+  // This can be used to e.g. implement support for a Retry-After header.
+  void SetCustomReleaseTime(const base::TimeTicks& release_time);
+
+  // Returns true if this object has no significant state (i.e. you could
+  // just as well start with a fresh BackoffEntry object), and hasn't
+  // had for Policy::entry_lifetime_ms.
+  bool CanDiscard() const;
+
+  // Resets this entry to a fresh (as if just constructed) state.
+  void Reset();
+
+  // Returns the failure count for this entry.
+  int failure_count() const { return failure_count_; }
+
+ protected:
+  // Equivalent to TimeTicks::Now(), virtual so unit tests can override.
+  virtual base::TimeTicks ImplGetTimeNow() const;
+
+ private:
+  // Calculates when requests should again be allowed through.
+  base::TimeTicks CalculateReleaseTime() const;
+
+  // Timestamp calculated by the exponential back-off algorithm at which we are
+  // allowed to start sending requests again.
+  base::TimeTicks exponential_backoff_release_time_;
+
+  // Counts request errors; decremented on success.
+  int failure_count_;
+
+  const Policy* const policy_;
+
+  DISALLOW_COPY_AND_ASSIGN(BackoffEntry);
+};
+
+}  // namespace net
+
+#endif  // NET_BASE_BACKOFF_ENTRY_H_