Really enable QUIC v40 and remove the old v40 flag.

Change-Id: I8d0df310e716f3663704f5bfb087ac85c7d1fb64
Reviewed-on: https://chromium-review.googlesource.com/663563Reviewed-by: Buck Krasic <ckrasic@chromium.org>
Commit-Queue: Ryan Hamilton <rch@chromium.org>
Cr-Commit-Position: refs/heads/master@{#501341}

net/quic/core/quic_flags_list.h

@@ -109,9 +109,6 @@ QUIC_FLAG(bool, FLAGS_quic_reloadable_flag_quic_enable_3rtos, false)
 // If true, enable experiment for testing PCC congestion-control.
 QUIC_FLAG(bool, FLAGS_quic_reloadable_flag_quic_enable_pcc, false)
 
-// If true, enable QUIC v40.
-QUIC_FLAG(bool, FLAGS_quic_enable_version_40, true)
-
 // In QUIC, QuicSession gets notified when stream frames are acked, discarded or
 // retransmitted.
 QUIC_FLAG(bool, FLAGS_quic_reloadable_flag_quic_use_stream_notifier2, true)
@@ -204,7 +201,7 @@ QUIC_FLAG(bool,
 
 // If true, QUIC v40 is enabled which includes changes to RST_STREAM, ACK
 // and STREAM frames match IETF format.
-QUIC_FLAG(bool, FLAGS_quic_reloadable_flag_quic_enable_version_40, false)
+QUIC_FLAG(bool, FLAGS_quic_reloadable_flag_quic_enable_version_40, true)
 
 // If true, QUIC can take ownership of data provided in a reference counted
 // memory to avoid data copy.