arc: Use GET_INTERFACE_FOR_METHOD macro

components/arc/audio/arc_audio_bridge.cc

Index: components/arc/audio/arc_audio_bridge.cc
diff --git a/components/arc/audio/arc_audio_bridge.cc b/components/arc/audio/arc_audio_bridge.cc
index dc037cb965ea4ae429f88ae860d02eafc1d1cc90..2a5263bdf47c95a9153a380792b99f6d1ea49ca7 100644
--- a/components/arc/audio/arc_audio_bridge.cc
+++ b/components/arc/audio/arc_audio_bridge.cc
@@ -11,14 +11,6 @@
 
 namespace arc {
 
-namespace {
-
-// Note: unlike most of our mojom definitions, AudioInstance::Init's minimum
-// version is not zero.
-constexpr uint32_t kMinInstanceVersionForInit = 1;
-
-}  // namespace
-
 ArcAudioBridge::ArcAudioBridge(ArcBridgeService* bridge_service)
     : ArcService(bridge_service), binding_(this) {
   arc_bridge_service()->audio()->AddObserver(this);
@@ -37,8 +29,7 @@ ArcAudioBridge::~ArcAudioBridge() {
 
 void ArcAudioBridge::OnInstanceReady() {
   mojom::AudioInstance* audio_instance =
-      arc_bridge_service()->audio()->GetInstanceForMethod(
-          "Init", kMinInstanceVersionForInit);
+      GET_INSTANCE_FOR_METHOD(arc_bridge_service()->audio(), Init);
   DCHECK(audio_instance);  // the instance on ARC side is too old.
   audio_instance->Init(binding_.CreateInterfacePtrAndBind());
 }
@@ -82,7 +73,7 @@ void ArcAudioBridge::SendSwitchState(bool headphone_inserted,
 
   VLOG(1) << "Send switch state " << switch_state;
   mojom::AudioInstance* audio_instance =
-      arc_bridge_service()->audio()->GetInstanceForMethod("NotifySwitchState");
+      GET_INSTANCE_FOR_METHOD(arc_bridge_service()->audio(), NotifySwitchState);
   if (audio_instance)
     audio_instance->NotifySwitchState(switch_state);
 }