Consolidate two IsArcWindow functions to reduce code duplication

components/arc/arc_util.cc

Index: components/arc/arc_util.cc
diff --git a/components/arc/arc_util.cc b/components/arc/arc_util.cc
index 7c3ee3f5a080b7e1b4d0b82dc0bbc686873c5b5e..963368e3bc4c366869ef303f26fcbfb5f94b2520 100644
--- a/components/arc/arc_util.cc
+++ b/components/arc/arc_util.cc
@@ -6,10 +6,13 @@
 
 #include <string>
 
+#include "ash/shared/app_types.h"
 #include "base/command_line.h"
 #include "base/feature_list.h"
 #include "chromeos/chromeos_switches.h"
 #include "components/user_manager/user_manager.h"
+#include "ui/aura/client/aura_constants.h"
+#include "ui/aura/window.h"
 
 namespace arc {
 
@@ -111,4 +114,11 @@ bool IsArcOptInVerificationDisabled() {
       chromeos::switches::kDisableArcOptInVerification);
 }
 
+bool IsArcAppWindow(aura::Window* window) {
+  if (!window)
+    return false;
+  return window->GetProperty(aura::client::kAppType) ==
+         static_cast<int>(ash::AppType::ARC_APP);
+}
+
 }  // namespace arc