Added log messages for important call setup events: first packet sent/received

webrtc/base/BUILD.gn

 # Copyright (c) 2014 The WebRTC project authors. All Rights Reserved.
 #
 # Use of this source code is governed by a BSD-style license
 # that can be found in the LICENSE file in the root of the source
 # tree. An additional intellectual property rights grant can be found
 # in the file PATENTS.  All contributing project authors may
 # be found in the AUTHORS file in the root of the source tree.
 
 import("//build/config/crypto.gni")
 import("//build/config/ui.gni")
@@ skipping 115 matching lines @@
     "event.h",
     "event_tracer.cc",
     "event_tracer.h",
     "exp_filter.cc",
     "exp_filter.h",
     "md5.cc",
     "md5.h",
     "md5digest.cc",
     "md5digest.h",
     "mod_ops.h",
+    "onetimeevent.h",
     "optional.h",
     "platform_file.cc",
     "platform_file.h",
     "platform_thread.cc",
     "platform_thread.h",
     "platform_thread_types.h",
     "random.cc",
     "random.h",
     "rate_statistics.cc",
     "rate_statistics.h",
@@ skipping 497 matching lines @@
       "objc/RTCUIApplication.mm",
     ]
   }
 }
 
 source_set("gtest_prod") {
   sources = [
     "gtest_prod_util.h",
   ]
 }