Introduced in #11369, this fixes an issue with the diff suppress function when creating a new `aws_db_instance` resource, while using the default `engine_version`.
```
$ make testacc TEST=./builtin/providers/aws TESTARGS='-run=TestAccAWSDBInstance_diffSuppressInitialState'
==> Checking that code complies with gofmt requirements...
go generate $(go list ./... | grep -v /terraform/vendor/)
2017/02/13 11:52:12 Generated command/internal_plugin_list.go
TF_ACC=1 go test ./builtin/providers/aws -v -run=TestAccAWSDBInstance_diffSuppressInitialState -timeout 120m
=== RUN TestAccAWSDBInstance_diffSuppressInitialState
--- PASS: TestAccAWSDBInstance_diffSuppressInitialState (480.78s)
PASS
ok github.com/hashicorp/terraform/builtin/providers/aws 480.793s
```
Jake Champlin