Add a histogram metric tracking for how long audio RTP packets are sent

webrtc/audio/BUILD.gn

 # Copyright (c) 2015 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("../webrtc.gni")
 if (is_android) {
   import("//build/config/android/config.gni")
   import("//build/config/android/rules.gni")
 }
 
 rtc_static_library("audio") {
   sources = [
     "audio_receive_stream.cc",
     "audio_receive_stream.h",
     "audio_send_stream.cc",
     "audio_send_stream.h",
     "audio_state.cc",
     "audio_state.h",
     "audio_transport_proxy.cc",
     "audio_transport_proxy.h",
     "conversion.h",
     "scoped_voe_interface.h",
+    "time_interval.cc",
+    "time_interval.h",
   ]
 
   if (!build_with_chromium && is_clang) {
     # Suppress warnings from the Chromium Clang plugin (bugs.webrtc.org/163).
     suppressed_configs += [ "//build/config/clang:find_bad_constructs" ]
   }
 
   deps = [
     "..:webrtc_common",
     "../api:audio_mixer_api",
@@ skipping 29 matching lines @@
     }
 
     # TODO(kjellander): Remove (bugs.webrtc.org/6828)
     # This needs remote_bitrate_estimator to be moved to webrtc/api first.
     check_includes = false
 
     sources = [
       "audio_receive_stream_unittest.cc",
       "audio_send_stream_unittest.cc",
       "audio_state_unittest.cc",
+      "time_interval_unittest.cc",
     ]
     deps = [
       ":audio",
       "../api:mock_audio_mixer",
       "../base:rtc_base_approved",
       "../base:rtc_task_queue",
       "../call:rtp_receiver",
       "../modules/audio_device:mock_audio_device",
       "../modules/audio_mixer:audio_mixer_impl",
       "../modules/congestion_controller:congestion_controller",
@@ skipping 38 matching lines @@
         "../../resources/voice_engine/audio_tiny48.wav",
       ]
 
       if (!build_with_chromium && is_clang) {
         # Suppress warnings from the Chromium Clang plugin (bugs.webrtc.org/163)
         suppressed_configs += [ "//build/config/clang:find_bad_constructs" ]
       }
     }
   }
 }