Change MNC codename to just M.

Change-Id: If86839c5d1f0bf4f013aa786ba2dc5bcb39527f8

samples/browseable/RuntimePermissionsBasic/src/com.example.android.basicpermissions/MainActivity.java

@@ -124,12 +124,6 @@ public class MainActivity extends Activity {
     }
 
     public static boolean isMNC() {
-        /*
-         TODO: In the Android M Preview release, checking if the platform is M is done through
-         the codename, not the version code. Once the API has been finalised, the following check
-         should be used: */
-        // return Build.VERSION.SDK_INT >= Build.VERSION_CODES.MNC
-
-        return "MNC".equals(Build.VERSION.CODENAME);
+        return Build.VERSION.SDK_INT >= Build.VERSION_CODES.M;
     }
 }