Always use arc::InstanceHolder<T>::GetInstanceForMethod

components/arc/power/arc_power_bridge.cc

Index: components/arc/power/arc_power_bridge.cc
diff --git a/components/arc/power/arc_power_bridge.cc b/components/arc/power/arc_power_bridge.cc
index fb8b1fdc7b0adfa8f37d807f9e71be051217d20b..abec9d75b79f5f30dfff12f36ca5dd14e5443a71 100644
--- a/components/arc/power/arc_power_bridge.cc
+++ b/components/arc/power/arc_power_bridge.cc
@@ -14,6 +14,12 @@
 
 namespace arc {
 
+namespace {
+
+constexpr uint32_t kMinVersionForSetInteractive = 1;
+
+}  // namespace
+
 ArcPowerBridge::ArcPowerBridge(ArcBridgeService* bridge_service)
     : ArcService(bridge_service), binding_(this) {
   arc_bridge_service()->power()->AddObserver(this);
@@ -26,12 +32,8 @@ ArcPowerBridge::~ArcPowerBridge() {
 
 void ArcPowerBridge::OnInstanceReady() {
   mojom::PowerInstance* power_instance =
-      arc_bridge_service()->power()->instance();
-  if (!power_instance) {
-    LOG(ERROR) << "OnPowerInstanceReady called, but no power instance found";
-    return;
-  }
-
+      arc_bridge_service()->power()->GetInstanceForMethod("Init");
+  DCHECK(power_instance);
   power_instance->Init(binding_.CreateInterfacePtrAndBind());
   ash::Shell::GetInstance()->display_configurator()->AddObserver(this);
 }
@@ -44,11 +46,10 @@ void ArcPowerBridge::OnInstanceClosed() {
 void ArcPowerBridge::OnPowerStateChanged(
     chromeos::DisplayPowerState power_state) {
   mojom::PowerInstance* power_instance =
-      arc_bridge_service()->power()->instance();
-  if (!power_instance) {
-    LOG(ERROR) << "PowerInstance is not available";
+      arc_bridge_service()->power()->GetInstanceForMethod(
+          "SetInteractive", kMinVersionForSetInteractive);
+  if (!power_instance)
     return;
-  }
 
   bool enabled = (power_state != chromeos::DISPLAY_POWER_ALL_OFF);
   power_instance->SetInteractive(enabled);