Roll src/net/third_party/quiche/src/ db0253c93..13ebfa60c (4 commits)

https://quiche.googlesource.com/quiche.git/+log/db0253c93b9b..13ebfa60c3f2

$ git log db0253c93..13ebfa60c --date=short --no-merges --format='%ad %ae %s'
2020-08-10 wub Deprecate --gfe2_reloadable_flag_quic_save_user_agent_in_quic_session.
2020-08-07 nharper Expose ProofSource::Details on QuicCryptoServerStream
2020-08-07 renjietang Add version DCHECKS in GOAWAY handling.
2020-08-07 nharper Tighten content-length header parsing in shared spdy code, not flag protected

Created with:
  roll-dep src/net/third_party/quiche/src src/third_party/quic_trace/src

remove deprecated flag

R=dschinazi@chromium.org

Change-Id: Ia065ee167b59261845f652258cbeb47584cd8a79
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2346909
Auto-Submit: Dan Zhang <danzh@chromium.org>
Commit-Queue: David Schinazi <dschinazi@chromium.org>
Reviewed-by: David Schinazi <dschinazi@chromium.org>
Cr-Commit-Position: refs/heads/master@{#796463}

DEPS

@@ -322,7 +322,7 @@ vars = {
   # Three lines of non-changing comments so that
   # the commit queue can handle CLs rolling feed
   # and whatever else without interference from each other.
-  'quiche_revision': 'db0253c93b9b0d15c859744cd242df4a7e4f6e09',
+  'quiche_revision': '13ebfa60c3f2970e5d7f05e85ccf29ce3c1304ba',
   # Three lines of non-changing comments so that
   # the commit queue can handle CLs rolling ios_webkit
   # and whatever else without interference from each other.

net/quic/quic_flags_list.h

@@ -301,11 +301,6 @@ QUIC_FLAG(bool,
           FLAGS_quic_reloadable_flag_quic_support_handshake_done_in_t050,
           true)
 
-// If true, save user agent into in QuicSession.
-QUIC_FLAG(bool,
-          FLAGS_quic_reloadable_flag_quic_save_user_agent_in_quic_session,
-          true)
-
 // When true, QUIC_CRYPTO versions of QUIC will not send the max ACK delay
 // unless it is configured to a non-default value.
 QUIC_FLAG(bool,