Geolocation: cleanup NetworkLocationProvider

device/geolocation/network_location_provider.h

 // 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 DEVICE_GEOLOCATION_NETWORK_LOCATION_PROVIDER_H_
 #define DEVICE_GEOLOCATION_NETWORK_LOCATION_PROVIDER_H_
 
 #include <stddef.h>
 
 #include <list>
 #include <map>
 #include <memory>
 
 #include "base/macros.h"
 #include "base/memory/ref_counted.h"
 #include "base/memory/weak_ptr.h"
 #include "base/strings/string16.h"
-#include "base/threading/non_thread_safe.h"
 #include "base/threading/thread.h"
+#include "base/threading/thread_checker.h"
 #include "device/geolocation/geolocation_export.h"
 #include "device/geolocation/geoposition.h"
 #include "device/geolocation/location_provider.h"
 #include "device/geolocation/network_location_request.h"
 #include "device/geolocation/wifi_data_provider_manager.h"
 
 namespace device {
 class AccessTokenStore;
 
-class NetworkLocationProvider : public base::NonThreadSafe,
-                                public LocationProvider {
+class NetworkLocationProvider : public LocationProvider {
  public:
   // Cache of recently resolved locations. Public for tests.
   class DEVICE_GEOLOCATION_EXPORT PositionCache {
    public:
     // The maximum size of the cache of positions.
     static const size_t kMaximumSize;
 
     PositionCache();
     ~PositionCache();
 
@@ skipping 23 matching lines @@
   };
 
   NetworkLocationProvider(
       const scoped_refptr<AccessTokenStore>& access_token_store,
       const scoped_refptr<net::URLRequestContextGetter>& context,
       const GURL& url,
       const base::string16& access_token);
   ~NetworkLocationProvider() override;
 
   // LocationProvider implementation
-  void SetUpdateCallback(
-      const LocationProviderUpdateCallback& callback) override;
+  void SetUpdateCallback(const LocationProviderUpdateCallback& cb) override;
   bool StartProvider(bool high_accuracy) override;
   void StopProvider() override;
   const Geoposition& GetPosition() override;
   void OnPermissionGranted() override;
 
  private:
-  // Satisfies a position request from cache or network.
+  // Tries to update |position_| request from cache or network.
   void RequestPosition();
 
-  // Gets called when new wifi data is available.
+  // Gets called when new wifi data is available, either via explicit request to
+  // or callback from |wifi_data_provider_manager_|.
   void OnWifiDataUpdate();
 
-  // Internal helper used by OnWifiDataUpdate.
-  void OnWifiDataUpdated();
-
   bool IsStarted() const;
 
   void OnLocationResponse(const Geoposition& position,
                           bool server_error,
                           const base::string16& access_token,
                           const WifiData& wifi_data);
 
   const scoped_refptr<AccessTokenStore> access_token_store_;
 
-  // The wifi data provider, acquired via global factories.
+  // The wifi data provider, acquired via global factories. Valid between
+  // StartProvider() and StopProvider(), and checked via IsStarted().
   WifiDataProviderManager* wifi_data_provider_manager_;
 
   WifiDataProviderManager::WifiDataUpdateCallback wifi_data_update_callback_;
 
   // The  wifi data and a flag to indicate if the data set is complete.
   WifiData wifi_data_;
   bool is_wifi_data_complete_;
 
   // The timestamp for the latest wifi data update.
   base::Time wifi_timestamp_;
 
   // Cached value loaded from the token store or set by a previous server
   // response, and sent in each subsequent network request.
   base::string16 access_token_;
 
   // The current best position estimate.
   Geoposition position_;
 
   LocationProvider::LocationProviderUpdateCallback
       location_provider_update_callback_;
 
   // Whether permission has been granted for the provider to operate.
   bool is_permission_granted_;
 
   bool is_new_data_available_;
 
   // The network location request object, and the url it uses.
-  std::unique_ptr<NetworkLocationRequest> request_;
+  const std::unique_ptr<NetworkLocationRequest> request_;
 
   // The cache of positions.
   const std::unique_ptr<PositionCache> position_cache_;
 
+  base::ThreadChecker thread_checker_;
+
   base::WeakPtrFactory<NetworkLocationProvider> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(NetworkLocationProvider);
 };
 
 // Factory functions for the various types of location provider to abstract
 // over the platform-dependent implementations.
 DEVICE_GEOLOCATION_EXPORT LocationProvider* NewNetworkLocationProvider(
     const scoped_refptr<AccessTokenStore>& access_token_store,
     const scoped_refptr<net::URLRequestContextGetter>& context,
     const GURL& url,
     const base::string16& access_token);
 
 }  // namespace device
 
 #endif  // DEVICE_GEOLOCATION_NETWORK_LOCATION_PROVIDER_H_