Remove voe::Statistics.

voice_engine/voice_engine_impl.cc

Index: voice_engine/voice_engine_impl.cc
diff --git a/voice_engine/voice_engine_impl.cc b/voice_engine/voice_engine_impl.cc
index 000907ea8da0edf26ff248cdb69a6fc8ed2a9f1d..681f00ed0b518a22b3f9d88a82cd06cc2665386e 100644
--- a/voice_engine/voice_engine_impl.cc
+++ b/voice_engine/voice_engine_impl.cc
@@ -65,7 +65,6 @@ std::unique_ptr<voe::ChannelProxy> VoiceEngineImpl::GetChannelProxy(
     int channel_id) {
   RTC_DCHECK(channel_id >= 0);
   rtc::CritScope cs(crit_sec());
-  RTC_DCHECK(statistics().Initialized());
   return std::unique_ptr<voe::ChannelProxy>(
       new voe::ChannelProxy(channel_manager().GetChannel(channel_id)));
 }