Replace FOR_EACH_OBSERVER in chromeos/ with range-based for

chromeos/dbus/cras_audio_client.cc

Index: chromeos/dbus/cras_audio_client.cc
diff --git a/chromeos/dbus/cras_audio_client.cc b/chromeos/dbus/cras_audio_client.cc
index e9957ec47a1071af85d595115689b14fe123fde0..acf24ed48000986a946047fe775bc0bfba902df7 100644
--- a/chromeos/dbus/cras_audio_client.cc
+++ b/chromeos/dbus/cras_audio_client.cc
@@ -279,7 +279,8 @@ class CrasAudioClientImpl : public CrasAudioClient {
 
   void NameOwnerChangedReceived(const std::string& old_owner,
                                 const std::string& new_owner) {
-    FOR_EACH_OBSERVER(Observer, observers_, AudioClientRestarted());
+    for (auto& observer : observers_)
+      observer.AudioClientRestarted();
   }
 
   // Called when a OutputMuteChanged signal is received.
@@ -292,7 +293,8 @@ class CrasAudioClientImpl : public CrasAudioClient {
       LOG(ERROR) << "Error reading signal from cras:"
                  << signal->ToString();
     }
-    FOR_EACH_OBSERVER(Observer, observers_, OutputMuteChanged(user_mute));
+    for (auto& observer : observers_)
+      observer.OutputMuteChanged(user_mute);
   }
 
   // Called when a InputMuteChanged signal is received.
@@ -303,11 +305,13 @@ class CrasAudioClientImpl : public CrasAudioClient {
       LOG(ERROR) << "Error reading signal from cras:"
                  << signal->ToString();
     }
-    FOR_EACH_OBSERVER(Observer, observers_, InputMuteChanged(mute));
+    for (auto& observer : observers_)
+      observer.InputMuteChanged(mute);
   }
 
   void NodesChangedReceived(dbus::Signal* signal) {
-    FOR_EACH_OBSERVER(Observer, observers_, NodesChanged());
+    for (auto& observer : observers_)
+      observer.NodesChanged();
   }
 
   void ActiveOutputNodeChangedReceived(dbus::Signal* signal) {
@@ -317,7 +321,8 @@ class CrasAudioClientImpl : public CrasAudioClient {
       LOG(ERROR) << "Error reading signal from cras:"
                  << signal->ToString();
     }
-    FOR_EACH_OBSERVER(Observer, observers_, ActiveOutputNodeChanged(node_id));
+    for (auto& observer : observers_)
+      observer.ActiveOutputNodeChanged(node_id);
   }
 
   void ActiveInputNodeChangedReceived(dbus::Signal* signal) {
@@ -327,7 +332,8 @@ class CrasAudioClientImpl : public CrasAudioClient {
       LOG(ERROR) << "Error reading signal from cras:"
                  << signal->ToString();
     }
-    FOR_EACH_OBSERVER(Observer, observers_, ActiveInputNodeChanged(node_id));
+    for (auto& observer : observers_)
+      observer.ActiveInputNodeChanged(node_id);
   }
 
   void OutputNodeVolumeChangedReceived(dbus::Signal* signal) {
@@ -341,8 +347,8 @@ class CrasAudioClientImpl : public CrasAudioClient {
     if (!reader.PopInt32(&volume)) {
       LOG(ERROR) << "Error eading signal from cras:" << signal->ToString();
     }
-    FOR_EACH_OBSERVER(Observer, observers_,
-                      OutputNodeVolumeChanged(node_id, volume));
+    for (auto& observer : observers_)
+      observer.OutputNodeVolumeChanged(node_id, volume);
   }
 
   void OnGetVolumeState(const GetVolumeStateCallback& callback,