Example Bluetooth ARC++ test changes.

components/arc/arc_bridge_service.h

Index: components/arc/arc_bridge_service.h
diff --git a/components/arc/arc_bridge_service.h b/components/arc/arc_bridge_service.h
index 7c29e78a4519ddfc433baf94fd0673b13b786578..a6eed3a0228558fcb3a8fac678691ee77e39495e 100644
--- a/components/arc/arc_bridge_service.h
+++ b/components/arc/arc_bridge_service.h
@@ -192,9 +192,7 @@ class ArcBridgeService : public mojom::ArcBridgeHost {
   mojom::AppInstance* app_instance() { return app_ptr_.get(); }
   mojom::AudioInstance* audio_instance() { return audio_ptr_.get(); }
   mojom::AuthInstance* auth_instance() { return auth_ptr_.get(); }
-  mojom::BluetoothInstance* bluetooth_instance() {
-    return bluetooth_ptr_.get();
-  }
+  virtual mojom::BluetoothInstance* bluetooth_instance();
   mojom::ClipboardInstance* clipboard_instance() {
     return clipboard_ptr_.get();
   }
@@ -229,7 +227,7 @@ class ArcBridgeService : public mojom::ArcBridgeHost {
 
   int32_t app_version() const { return app_ptr_.version(); }
   int32_t audio_version() const { return audio_ptr_.version(); }
-  int32_t bluetooth_version() const { return bluetooth_ptr_.version(); }
+  virtual int32_t bluetooth_version() const;
   int32_t auth_version() const { return auth_ptr_.version(); }
   int32_t clipboard_version() const { return clipboard_ptr_.version(); }
   int32_t crash_collector_version() const {