diff --git a/core/java/android/app/BackStackRecord.java b/core/java/android/app/BackStackRecord.java
index cf794c5..6b16e8f 100644
--- a/core/java/android/app/BackStackRecord.java
+++ b/core/java/android/app/BackStackRecord.java
@@ -349,7 +349,9 @@
 
     public BackStackRecord(FragmentManagerImpl manager) {
         mManager = manager;
-        mAllowOptimization = Build.isAtLeastO();
+        int targetSdkVersion = manager.mHost.getContext().getApplicationInfo().targetSdkVersion;
+        // TODO: make the check N_MR1 or O
+        mAllowOptimization = targetSdkVersion > Build.VERSION_CODES.N;
     }
 
     public int getId() {
diff --git a/core/java/android/os/Build.java b/core/java/android/os/Build.java
index e5832c8..0d6d369 100644
--- a/core/java/android/os/Build.java
+++ b/core/java/android/os/Build.java
@@ -924,16 +924,4 @@
             return -1;
         }
     }
-
-    /**
-     * Check if the device is running on the Android O release or newer.
-     *
-     * @return {@code true} if O APIs are available for use
-     *
-     * @hide
-     */
-    public static boolean isAtLeastO() {
-        return !"REL".equals(VERSION.CODENAME)
-                && "O".compareTo(VERSION.CODENAME) <= 0;
-    }
 }