x/net/http2: TestTransportFailureErrorForHTTP1Response/with_enough_frame_size_to_start_reading failures

[gopherbot]

#!watchflakes
default <- pkg == "golang.org/x/net/http2" && test == "TestTransportFailureErrorForHTTP1Response/with_enough_frame_size_to_start_reading"

Issue created automatically to collect these failures.

Example (log):

=== RUN   TestTransportFailureErrorForHTTP1Response/with_enough_frame_size_to_start_reading
    transport_test.go:311: expected error to contain "frame header looked like an HTTP/1.1 header", got http2: client conn could not be established
--- FAIL: TestTransportFailureErrorForHTTP1Response/with_enough_frame_size_to_start_reading (0.00s)

— watchflakes