chore(migration): Migrate code from googleapis/python-storage into packages/google-cloud-storage (#16192)

See #10956. 

This PR should be merged with a merge-commit, not a squash-commit, in
order to preserve the git history.

Author: parthea

.librarian/config.yaml

@@ -12,3 +12,7 @@ libraries:
 # `google-django-spanner` is blocked until the presubmits are green.
   - id: "google-django-spanner"
     release_blocked: true
+# TODO(https://github.com/googleapis/google-cloud-python/issues/16487):
+# Allow releases for google-cloud-storage once this bug is fixed.
+  - id: "google-cloud-storage"
+    release_blocked: true