Refactor DBusThreadManager to split away BT clients.

device/bluetooth/bluetooth_gatt_connection_chromeos.h

Index: device/bluetooth/bluetooth_gatt_connection_chromeos.h
diff --git a/device/bluetooth/bluetooth_gatt_connection_chromeos.h b/device/bluetooth/bluetooth_gatt_connection_chromeos.h
index f6c746964a551cc6e9fdf024f9794ee307418428..04b24c32d0d95dbff56d64985f834ed820506200 100644
--- a/device/bluetooth/bluetooth_gatt_connection_chromeos.h
+++ b/device/bluetooth/bluetooth_gatt_connection_chromeos.h
@@ -9,9 +9,9 @@
 
 #include "base/callback.h"
 #include "base/memory/weak_ptr.h"
-#include "chromeos/dbus/bluetooth_device_client.h"
 #include "dbus/object_path.h"
 #include "device/bluetooth/bluetooth_gatt_connection.h"
+#include "device/bluetooth/dbus/bluetooth_device_client.h"
 
 namespace device {
 
@@ -25,7 +25,7 @@ namespace chromeos {
 // Chrome OS platform.
 class BluetoothGattConnectionChromeOS
     : public device::BluetoothGattConnection,
-      public BluetoothDeviceClient::Observer {
+      public bluez::BluetoothDeviceClient::Observer {
  public:
   explicit BluetoothGattConnectionChromeOS(
       scoped_refptr<device::BluetoothAdapter> adapter,
@@ -39,8 +39,7 @@ class BluetoothGattConnectionChromeOS
   void Disconnect() override;
 
  private:
-
-  // chromeos::BluetoothDeviceClient::Observer overrides.
+  // bluez::Bluetooth$1Client::Observer overrides.
   void DeviceRemoved(const dbus::ObjectPath& object_path) override;
   void DevicePropertyChanged(const dbus::ObjectPath& object_path,
                              const std::string& property_name) override;