Use LegacySerializedResponse in Header transport
Use LegacySerializedResponse in Header transport

Summary: Use LegacySerializedResponse and ResponsePayload in Header transport. In the case of Header we know we always want the envelope.

Reviewed By: yfeldblum

Differential Revision: D28976685

fbshipit-source-id: 064f441ee13c3e63aa164580806c2546501b483b

facebook/fbthrift,facebook/fbthrift,facebook/fbthrift,facebook/fbthrift,facebook/fbthrift,facebook/fbthrift,facebook/fbthrift,facebook/fbthrift,facebook/fbthrift