Mark QUIC broken when the network blackholes after the handshake

net/http/http_network_transaction.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "net/http/http_network_transaction.h"
 
 #include <memory>
 #include <set>
 #include <utility>
 #include <vector>
@@ skipping 1515 matching lines @@
     // ERR_EMPTY_RESPONSE. This may still be close/reuse race if the socket was
     // preconnected but failed to be used before the server timed it out.
     case ERR_EMPTY_RESPONSE:
       if (ShouldResendRequest()) {
         net_log_.AddEventWithNetErrorCode(
             NetLogEventType::HTTP_TRANSACTION_RESTART_AFTER_ERROR, error);
         ResetConnectionAndRequestForResend();
         error = OK;
       }
       break;
+    case ERR_QUIC_BROKEN_ERROR:
+      DCHECK(GetResponseHeaders() == nullptr);

[Jana, 2017/04/06 02:29:18]

why is this a DCHECK and not if (ShouldResendRequest())?

[Ryan Hamilton, 2017/04/06 03:43:38]

Because this error code is never returned when headers have been received. And
I'm not checking ShouldResendRequest (which an earlier patch set did) because it
turns out that HandleIOError is not called after headers have been received, so
it's rather redundant.

+      net_log_.AddEventWithNetErrorCode(
+          NetLogEventType::HTTP_TRANSACTION_RESTART_AFTER_ERROR, error);
+      ResetConnectionAndRequestForResend();
+      error = OK;
+      break;
     case ERR_SPDY_PING_FAILED:
     case ERR_SPDY_SERVER_REFUSED_STREAM:
     case ERR_QUIC_HANDSHAKE_FAILED:
       net_log_.AddEventWithNetErrorCode(
           NetLogEventType::HTTP_TRANSACTION_RESTART_AFTER_ERROR, error);
       ResetConnectionAndRequestForResend();
       error = OK;
       break;
     case ERR_MISDIRECTED_REQUEST:
       // If this is the second try, just give up.
@@ skipping 166 matching lines @@
   DCHECK(stream_request_);
 
   // Since the transaction can restart with auth credentials, it may create a
   // stream more than once. Accumulate all of the connection attempts across
   // those streams by appending them to the vector:
   for (const auto& attempt : stream_request_->connection_attempts())
     connection_attempts_.push_back(attempt);
 }
 
 }  // namespace net