I have done some searching but, I don't see a way to add files from Google Cloud Storage to Google Drive other than doing downloading and uploading them. Also AFAIK, gsutil, which Google Cloud Storage APIs can interact with, also supports downloading and uploading of files when sharing to other storage.
And, as answered in Cloud Storage - Frequently Asked Questions, Google Drive and Google Cloud Storage are two different storage services wherein both allow programmatic access to their functionality, but the goals of the APIs are quite different.
However, you may want to try using Request Endpoints wherein you can access Google Cloud Storage through three request endpoints (URIs). Which one you use depends on the operation you are performing.
IMPORTANT NOTE: The Google Cloud Storage URIs described on this page are subject to change.
You can use the following URLs to access an object:
XML API
storage.googleapis.com/<bucket>/<object>
<bucket>.storage.googleapis.com/<object>
JSON API
www.googleapis.com/download/storage/v1/b/<bucket>/o/<object-encoded-as-URL-path-segment>?alt=media
These URLs support secure sockets layer (SSL) encryption, which means you can use either HTTP or HTTPS. If you authenticate to the Google Cloud Storage API using OAuth 2.0, you should use HTTPS.
You may want to also check Sharing and Collaboration for more information.