Add clock to ACM config struct

The purpose is to clean up the ACM interface a bit. This is a
follow-up of a comment in http://review.webrtc.org/13379004/.

R=turaj@webrtc.org

Review URL: https://webrtc-codereview.appspot.com/16389005

git-svn-id: http://webrtc.googlecode.com/svn/trunk@6006 4adac7df-926f-26a2-2b94-8c16560cd09d
diff --git a/webrtc/modules/audio_coding/main/acm2/acm_receiver.h b/webrtc/modules/audio_coding/main/acm2/acm_receiver.h
index 089016a..7a238ae 100644
--- a/webrtc/modules/audio_coding/main/acm2/acm_receiver.h
+++ b/webrtc/modules/audio_coding/main/acm2/acm_receiver.h
@@ -27,7 +27,6 @@
 
 namespace webrtc {
 
-class Clock;
 struct CodecInst;
 class CriticalSectionWrapper;
 class RWLockWrapper;
@@ -48,7 +47,7 @@
   };
 
   // Constructor of the class
-  explicit AcmReceiver(const AudioCodingModule::Config& config, Clock* clock);
+  explicit AcmReceiver(const AudioCodingModule::Config& config);
 
   // Destructor of the class.
   ~AcmReceiver();