fs: always return promise from openAsBlob()

Wrap path validation and blob creation
in try/catch. Any synchronous errors
become Promise rejections. Ensures the
function always returns a Promise.

Fixes: #62418

Author: mattskel

lib/fs.js

@@ -574,8 +574,12 @@ function openAsBlob(path, options = kEmptyObject) {
   // The underlying implementation here returns the Blob synchronously for now.
   // To give ourselves flexibility to maybe return the Blob asynchronously,
   // this API returns a Promise.
-  path = getValidatedPath(path);
-  return PromiseResolve(createBlobFromFilePath(path, { type }));
+  try {
+    path = getValidatedPath(path);
+    return PromiseResolve(createBlobFromFilePath(path, { type }));
+  } catch (error) {
+    return Promise.reject(error);
+  }
 }
 
 /**