Remove CommandLine dependency from the Linux's AudioCapturer.

remoting/host/audio_capturer_mac.cc

Index: remoting/host/audio_capturer_mac.cc
diff --git a/remoting/host/audio_capturer_mac.cc b/remoting/host/audio_capturer_mac.cc
index 1db67c25a05954fd8916cea9f62c3a61224bc28d..a00acf491b7b5b33a1cebbd33c08561398cedfde 100644
--- a/remoting/host/audio_capturer_mac.cc
+++ b/remoting/host/audio_capturer_mac.cc
@@ -7,11 +7,12 @@
 
 namespace remoting {
 
-bool AudioCapturer::IsSupported() {
+bool AudioCapturer::IsSupported(ChromotingHostContext* context) {
   return false;
 }
 
-scoped_ptr<AudioCapturer> AudioCapturer::Create() {
+scoped_ptr<AudioCapturer> AudioCapturer::Create(
+    ChromotingHostContext* context) {
   NOTIMPLEMENTED();
   return scoped_ptr<AudioCapturer>(NULL);
 }