Add IPV4_FLAG_{DF,MF} constants.

Bug: 258093642
Test: see other CL in topic
Change-Id: I04b954a7adb0a0e8bc4032a2cbfc899fe958b3b1
diff --git a/staticlibs/framework/com/android/net/module/util/NetworkStackConstants.java b/staticlibs/framework/com/android/net/module/util/NetworkStackConstants.java
index ebef155..287473e 100644
--- a/staticlibs/framework/com/android/net/module/util/NetworkStackConstants.java
+++ b/staticlibs/framework/com/android/net/module/util/NetworkStackConstants.java
@@ -97,6 +97,8 @@
     public static final int IPV4_SRC_ADDR_OFFSET = 12;
     public static final int IPV4_DST_ADDR_OFFSET = 16;
     public static final int IPV4_ADDR_LEN = 4;
+    public static final int IPV4_FLAG_MF = 0x2000;
+    public static final int IPV4_FLAG_DF = 0x4000;
     public static final Inet4Address IPV4_ADDR_ALL = makeInet4Address(
             (byte) 0xff, (byte) 0xff, (byte) 0xff, (byte) 0xff);
     public static final Inet4Address IPV4_ADDR_ANY = makeInet4Address(