Wrap icon in Center widget

@@ -169,11 +169,14 @@ class ToggleFlashlightButton extends StatelessWidget {
           case TorchState.unavailable:
           case TorchState.unavailable:
             return const SizedBox(
             return const SizedBox(
               width: 48.0,
               width: 48.0,
+              child: Center(
                 child: Icon(
                 child: Icon(
                   Icons.no_flash,
                   Icons.no_flash,
                   size: 32.0,
                   size: 32.0,
                   color: Colors.grey,
                   color: Colors.grey,
-                ));
+                ),
+              ),
+            );
         }
         }
       },
       },
     );
     );