Refactor bluetooth_low_energy_win to prepare for new Bluetooth test fixture

device/bluetooth/bluetooth_task_manager_win.cc

Index: device/bluetooth/bluetooth_task_manager_win.cc
diff --git a/device/bluetooth/bluetooth_task_manager_win.cc b/device/bluetooth/bluetooth_task_manager_win.cc
index a3c75b66ebb679cccdb66a39d59d8297cbc42276..3a607a033f0bf3d66a5ac9502af9ba02797515a3 100644
--- a/device/bluetooth/bluetooth_task_manager_win.cc
+++ b/device/bluetooth/bluetooth_task_manager_win.cc
@@ -480,7 +480,8 @@ bool BluetoothTaskManagerWin::SearchLowEnergyDevices(
   ScopedVector<win::BluetoothLowEnergyDeviceInfo> btle_devices;
   std::string error;
   bool success =
-      win::EnumerateKnownBluetoothLowEnergyDevices(&btle_devices, &error);
+      win::BluetoothLowEnergyHub::GetInstance()
+          ->EnumerateKnownBluetoothLowEnergyDevices(&btle_devices, &error);
   if (!success) {
     LogPollingError(error.c_str(), 0);
     return false;
@@ -636,8 +637,9 @@ bool BluetoothTaskManagerWin::DiscoverLowEnergyDeviceServices(
 
   std::string error;
   ScopedVector<win::BluetoothLowEnergyServiceInfo> services;
-  bool success = win::EnumerateKnownBluetoothLowEnergyServices(
-      device_path, &services, &error);
+  bool success = win::BluetoothLowEnergyHub::GetInstance()
+                     ->EnumerateKnownBluetoothLowEnergyServices(
+                         device_path, &services, &error);
   if (!success) {
     LogPollingError(error.c_str(), 0);
     return false;