Simple dump for Virtual Caemra device

Bug: 301023410
Test: atest VirtualCameraDeviceTest#dump
Change-Id: I917c73c587ea246aeb44f8d6ca0ba03ca43f87dc
diff --git a/services/camera/virtualcamera/VirtualCameraService.h b/services/camera/virtualcamera/VirtualCameraService.h
index 2121d64..f04acb5 100644
--- a/services/camera/virtualcamera/VirtualCameraService.h
+++ b/services/camera/virtualcamera/VirtualCameraService.h
@@ -75,6 +75,9 @@
     mVerifyEglExtensions = false;
   }
 
+  // Default virtual device id (the host device id)
+  static constexpr int kDefaultDeviceId = 0;
+
  private:
   // Create and enable test camera instance if there's none.
   binder_status_t enableTestCameraCmd(