Update VPN isolation code for excluded routes

Bug: 230058738
Test: atest LinkPropertiesTest

Result: https://paste.googleplex.com/4706859672928256

Change-Id: I970fca6b0e2cd358e9bd77152563d13367867c74
(cherry picked from commit 2b97bbebf4b85e0024fc75298e760fc03516be40)
Merged-In: I970fca6b0e2cd358e9bd77152563d13367867c74
diff --git a/tests/common/java/android/net/LinkPropertiesTest.java b/tests/common/java/android/net/LinkPropertiesTest.java
index 8fc636a..345a78d 100644
--- a/tests/common/java/android/net/LinkPropertiesTest.java
+++ b/tests/common/java/android/net/LinkPropertiesTest.java
@@ -1261,6 +1261,17 @@
         assertFalse(lp.hasIpv4UnreachableDefaultRoute());
     }
 
+    @Test @IgnoreUpTo(Build.VERSION_CODES.S_V2)
+    public void testHasExcludeRoute() {
+        LinkProperties lp = new LinkProperties();
+        lp.setInterfaceName("VPN");
+        lp.addRoute(new RouteInfo(new IpPrefix(ADDRV4, 2), RTN_UNICAST));
+        lp.addRoute(new RouteInfo(new IpPrefix(ADDRV6, 0), RTN_UNICAST));
+        assertFalse(lp.hasExcludeRoute());
+        lp.addRoute(new RouteInfo(new IpPrefix(ADDRV6, 2), RTN_THROW));
+        assertTrue(lp.hasExcludeRoute());
+    }
+
     @Test @IgnoreUpTo(Build.VERSION_CODES.Q)
     @EnableCompatChanges({LinkProperties.EXCLUDED_ROUTES})
     public void testRouteAddWithSameKey() throws Exception {