backupupload: it is either result or message

src/backups.js

@@ -727,8 +727,8 @@ function runBackupUpload(uploadConfig, progressCallback, callback) {
         }
 
         callback();
-    }).on('message', function (progress) { // script sends either 'message' or 'result' property
-        if (!progress.result) return progressCallback({ message: `${progress.message} (${progressTag})` });
+    }).on('message', function (progress) { // this is { message } or { result }
+        if ('message' in progress) return progressCallback({ message: `${progress.message} (${progressTag})` });
         debug(`runBackupUpload: result - ${JSON.stringify(progress)}`);
         result = progress.result;
     });

src/scripts/backupupload.js

@@ -58,9 +58,7 @@ initialize(function (error) {
     if (error) throw error;
 
     backups.upload(backupId, format, dataLayoutString, throttledProgressCallback(5000), function resultHandler(error) {
-        if (error) debug('upload completed with error', error);
-
-        debug('upload completed');
+        debug('upload completed. error: ', error);
 
         process.send({ result: error ? error.message : '' });