Replace AudioScheduler with AudioPump.

remoting/host/audio_capturer_linux.cc

Index: remoting/host/audio_capturer_linux.cc
diff --git a/remoting/host/audio_capturer_linux.cc b/remoting/host/audio_capturer_linux.cc
index a34293a57e3d3a8f45c17494ade2bd5db6d7f9a0..8980a8dbe4b5b6160d5476569b978664130ba17c 100644
--- a/remoting/host/audio_capturer_linux.cc
+++ b/remoting/host/audio_capturer_linux.cc
@@ -37,6 +37,7 @@ AudioCapturerLinux::AudioCapturerLinux(
 }
 
 AudioCapturerLinux::~AudioCapturerLinux() {
+  pipe_reader_->RemoveObserver(this);
 }
 
 bool AudioCapturerLinux::Start(const PacketCapturedCallback& callback) {
@@ -47,15 +48,6 @@ bool AudioCapturerLinux::Start(const PacketCapturedCallback& callback) {
   return true;
 }
 
-void AudioCapturerLinux::Stop() {
-  pipe_reader_->RemoveObserver(this);
-  callback_.Reset();
-}
-
-bool AudioCapturerLinux::IsStarted() {
-  return !callback_.is_null();
-}
-
 void AudioCapturerLinux::OnDataRead(
     scoped_refptr<base::RefCountedString> data) {
   DCHECK(!callback_.is_null());