Fix failing test on storage_object_acl.
Fix failing test on storage_object_acl.

The `predefined_acl` test for `storage_object_acl` was failing. This is
because we removed the state-setting portion of the `predefined_acl`
field from `storage_bucket_acl`, and due to what I can only assume is a
copy/paste error, `storage_object_acl` was calling the Read function of
`storage_bucket_acl` instead of its own when using `predefined_acl`.

Updating to use `storage_object_acl`'s Read function makes the tests
pass.

selmanj/terraform-provider-google,hashicorp/terraform-provider-google,hashicorp/terraform-provider-google-beta,ubschmidt2/terraform-provider-google,terraform-providers/terraform-provider-google,rosbo/terraform-provider-google,hashicorp/terraform-provider-google-beta,terraform-providers/terraform-provider-google,drebes/terraform-provider-google,nickithewatt/terraform-provider-google,rosbo/terraform-provider-google,drebes/terraform-provider-google,hashicorp/terraform-provider-google-beta,hashicorp/terraform-provider-google,hashicorp/terraform-provider-google-beta,nickithewatt/terraform-provider-google,rosbo/terraform-provider-google,selmanj/terraform-provider-google,rosbo/terraform-provider-google,terraform-providers/terraform-provider-google,nickithewatt/terraform-provider-google,ubschmidt2/terraform-provider-google,terraform-providers/terraform-provider-google,terraform-providers/terraform-provider-google,drebes/terraform-provider-google,drebes/terraform-provider-google,hashicorp/terraform-provider-google,hashicorp/terraform-provider-google,ubschmidt2/terraform-provider-google,ubschmidt2/terraform-provider-google,selmanj/terraform-provider-google