Fix test 4.2 to test for stream error
Fix test 4.2 to test for stream error

The test sends an oversized data frame, so the server is required
to reset the stream with FRAME_SIZE_ERROR.
The server may treat this error as fatal for the connection and send
GOAWAY( FRAME_SIZE_ERROR ), or drop the connection instead.

These upgraded errors are already handled by TestStreamError

rmoorman/h2spec,shane-kearns/h2spec,summerwind/h2spec