add change long for
### SDK Features
### SDK Enhancements
+* `private/model/api`: Add EventStream support over RPC protocl ([#1998](https://github.com/aws/aws-sdk-go/pull/1998))
+ * Adds support for EventStream over JSON PRC protocol. This adds support for the EventStream's initial-response event, EventStream headers, and EventStream modeled exceptions. Also replaces the hand written tests with generated tests for EventStream usage.
### SDK Bugs
