Fix instacrash on bridgeless due to calling showMessage on null insta…

…nce (#39834)

Summary:
Pull Request resolved: #39834

Bridgeless is instacrashing on fast-refresh. This fixes it.

Changelog:
[Android] [Fixed] - Fix instacrash on bridgeless due to calling showMessage on null instance

Reviewed By: cipolleschi

Differential Revision: D49929822

fbshipit-source-id: a2ce65797abd34d6a3e2b7f2c50d38a62ea8bdea

packages/react-native/ReactAndroid/src/main/java/com/facebook/react/modules/devloading/DevLoadingModule.java

@@ -46,7 +46,9 @@ public void showMessage(final String message, final Double color, final Double b
         new Runnable() {
           @Override
           public void run() {
-            mDevLoadingViewManager.showMessage(message);
+            if (mDevLoadingViewManager != null) {
+              mDevLoadingViewManager.showMessage(message);
+            }
           }
         });
   }