[dist4]message_header  // num_bytes
[u4]0                  // version
[u4]0                  // interface ID
[u4]15                 // name
[u4]0                  // flags
[u4]0                  // padding
[anchr]message_header

[dist4]method15_params // num_bytes
[u4]0                  // version
[dist8]enum_array_0    // param0
[u8]0                  // param1
[anchr]method15_params

[anchr]enum_array_0
[dist4]enum_array_0_member  // num_bytes
[u4]0                       // num_elements
[anchr]enum_array_0_member

[u8]0x5678                  // This is not part of the array above (which is
                            // empty), so enum validation shouldn't be done on
                            // it.