Geolocation: cleanup NetworkLocationProvider

device/geolocation/network_location_provider.h

Index: device/geolocation/network_location_provider.h
diff --git a/device/geolocation/network_location_provider.h b/device/geolocation/network_location_provider.h
index dc3fb217f7f02ee2cea4df46e978b68cb2b936ac..634da9a966586d9da773fdab28217e6163525bce 100644
--- a/device/geolocation/network_location_provider.h
+++ b/device/geolocation/network_location_provider.h
@@ -15,8 +15,8 @@
 #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"
@@ -26,8 +26,7 @@
 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 {
@@ -71,23 +70,20 @@ class NetworkLocationProvider : public base::NonThreadSafe,
   ~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,
@@ -97,7 +93,8 @@ class NetworkLocationProvider : public base::NonThreadSafe,
 
   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_;
@@ -125,11 +122,13 @@ class NetworkLocationProvider : public base::NonThreadSafe,
   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);