Remove HTTP pipelining support.

net/base/net_log_event_type_list.h

 // 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.
 
 // NOTE: No header guards are used, since this file is intended to be expanded
 // directly into net_log.h. DO NOT include this file anywhere else.
 
 // In the event of a failure, a many end events will have a |net_error|
 // parameter with the integer error code associated with the failure.  Most
 // of these parameters are not individually documented.
@@ skipping 1881 matching lines @@
 
 // This event is created when a CertVerifier request attaches to a job.
 //
 // The event parameters are:
 //   {
 //      "source_dependency": <Source identifer for the job we are bound to>,
 //   }
 EVENT_TYPE(CERT_VERIFIER_REQUEST_BOUND_TO_JOB)
 
 // ------------------------------------------------------------------------
-// HttpPipelinedConnection
-// ------------------------------------------------------------------------
-
-// The start/end of a HttpPipelinedConnection.
-//   {
-//     "host_and_port": <The host-port string>,
-//   }
-EVENT_TYPE(HTTP_PIPELINED_CONNECTION)
-
-// This event is created when a pipelined connection finishes sending a request.
-//   {
-//     "source_dependency": <Source id of the requesting stream>,
-//   }
-EVENT_TYPE(HTTP_PIPELINED_CONNECTION_SENT_REQUEST)
-
-// This event is created when a pipelined connection finishes receiving the
-// response headers.
-//   {
-//     "source_dependency": <Source id of the requesting stream>,
-//     "feedback": <The value of HttpPipelinedConnection::Feedback indicating
-//                  pipeline capability>,
-//   }
-EVENT_TYPE(HTTP_PIPELINED_CONNECTION_RECEIVED_HEADERS)
-
-// This event is created when a pipelined stream closes.
-//   {
-//     "source_dependency": <Source id of the requesting stream>,
-//     "must_close": <True if the pipeline must shut down>,
-//   }
-EVENT_TYPE(HTTP_PIPELINED_CONNECTION_STREAM_CLOSED)
-
-// ------------------------------------------------------------------------
 // Download start events.
 // ------------------------------------------------------------------------
 
 // This event is created when a download is started, and lets the URL request
 // event source know what download source it is using.
 //   {
 //     "source_dependency": <Source id of the download>,
 //   }
 EVENT_TYPE(DOWNLOAD_STARTED)
 
@@ skipping 371 matching lines @@
 // entry.  It contains no parameters.
 EVENT_TYPE(SIMPLE_CACHE_ENTRY_CLOSE_BEGIN)
 
 // This event is created when the Simple Cache finishes a CloseEntry call.  It
 // contains no parameters.
 EVENT_TYPE(SIMPLE_CACHE_ENTRY_CLOSE_END)
 
 // This event is created (in a source of the same name) when the internal DNS
 // resolver creates a UDP socket to check for global IPv6 connectivity.
 EVENT_TYPE(IPV6_REACHABILITY_CHECK)