Options for handling the KmsKey setting for Google Cloud
Storage objects.
Values:
KMS_KEY_UNSPECIFIED (0):
KmsKey behavior is unspecified.
KMS_KEY_DESTINATION_BUCKET_DEFAULT (1):
Use the destination bucket's default
encryption settings.
KMS_KEY_PRESERVE (2):
Preserve the object's original Cloud KMS
customer-managed encryption key (CMEK) if
present. Objects that do not use a Cloud KMS
encryption key will be encrypted using the
destination bucket's encryption settings.
