Moved data reduction proxy initialization logic to ProfileImplIOData

components/data_reduction_proxy/browser/data_reduction_proxy_usage_stats.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 COMPONENTS_DATA_REDUCTION_PROXY_BROWSER_DATA_REDUCTION_PROXY_USAGE_STATS_H_
 #define COMPONENTS_DATA_REDUCTION_PROXY_BROWSER_DATA_REDUCTION_PROXY_USAGE_STATS_H_
 
+#include "base/callback.h"
 #include "base/message_loop/message_loop_proxy.h"
 #include "base/threading/thread_checker.h"
 #include "components/data_reduction_proxy/browser/data_reduction_proxy_params.h"
 #include "net/base/host_port_pair.h"
 #include "net/base/network_change_notifier.h"
 
 namespace data_reduction_proxy {
 
 class DataReductionProxyUsageStats
     : public net::NetworkChangeNotifier::NetworkChangeObserver {
  public:
-  // MessageLoopProxy instances are owned by io_thread. |params| outlives
+  // MessageLoopProxy instance is owned by io_thread. |params| outlives
   // this class instance.
   DataReductionProxyUsageStats(DataReductionProxyParams* params,
-                               base::MessageLoopProxy* ui_thread_proxy,
-                               base::MessageLoopProxy* io_thread_proxy);
+                               base::MessageLoopProxy* ui_thread_proxy);
   virtual ~DataReductionProxyUsageStats();
 
-  /**
-   * Callback intended to be called from |ChromeNetworkDelegate| when a
-   * request completes. This method is used to gather usage stats.
-   */
+  // Sets the callback to be called on the UI thread when the unavailability
+  // status has changed.
+  void set_unavailable_callback(
+      const base::Callback<void(bool)>& unavailable_callback) {
+    unavailable_callback_ = unavailable_callback;
+  }
+
+  // Callback intended to be called from |ChromeNetworkDelegate| when a
+  // request completes. This method is used to gather usage stats.
   void OnUrlRequestCompleted(const net::URLRequest* request, bool started);
 
-  /**
-   * Determines whether the data reduction proxy is unreachable.
-   * Returns true if data reduction proxy is unreachable.
-   */
-  bool isDataReductionProxyUnreachable();
+ private:
+  // NetworkChangeNotifier::NetworkChangeObserver:
+  virtual void OnNetworkChanged(
+      net::NetworkChangeNotifier::ConnectionType type) OVERRIDE;
 
- private:
+  // Counts requests that went through the data reduction proxy and counts
+  // requests that were eligible to go through the proxy.
+  void IncrementRequestCounts(bool actual);
+  void ClearRequestCounts();
+
+  // Checks if the availability status of the data reduction proxy has changed,
+  // and notifies the UIThread via NotifyUnavailabilityOnUIThread if so. The
+  // data reduction proxy is considered unavailable if and only if no requests
+  // went through the proxy but some eligible requests were service by other
+  // routes.
+  void MaybeNotifyUnavailability();
+  void NotifyUnavailabilityOnUIThread(bool unavailable);
+
   DataReductionProxyParams* data_reduction_proxy_params_;
   base::MessageLoopProxy* ui_thread_proxy_;
-  base::MessageLoopProxy* io_thread_proxy_;
 
   // The following 2 fields are used to determine if data reduction proxy is
   // unreachable. We keep a count of requests which should go through
   // data request proxy, as well as those which actually do. The proxy is
   // unreachable if no successful requests are made through it despite a
   // non-zero number of requests being eligible.
 
   // Count of requests which will be tried to be sent through data reduction
   // proxy. The count is only based on the config and not the bad proxy list.
   // Explicit bypasses are not part of this count. This is the desired behavior
   // since otherwise both counts would be identical.
   unsigned long eligible_num_requests_through_proxy_;
-  // Count of successfull requests through data reduction proxy.
+
+  // Count of successful requests through data reduction proxy.
   unsigned long actual_num_requests_through_proxy_;
 
-  // NetworkChangeNotifier::NetworkChangeObserver:
-  virtual void OnNetworkChanged(
-      net::NetworkChangeNotifier::ConnectionType type) OVERRIDE;
-
-  void IncRequestCountsOnUiThread(bool actual);
-  void ClearRequestCountsOnUiThread();
+  // Whether or not the data reduction proxy is unavailable.
+  bool unavailable_;
 
   base::ThreadChecker thread_checker_;
 
+  // Called when the unavailability status has changed. Runs on the UI thread.
+  base::Callback<void(bool)> unavailable_callback_;
+
   DISALLOW_COPY_AND_ASSIGN(DataReductionProxyUsageStats);
 };
 
 }  // namespace data_reduction_proxy
 
 #endif  // COMPONENTS_DATA_REDUCTION_PROXY_BROWSER_DATA_REDUCTION_PROXY_USAGE_STATS_H_