Wipe the data in IpMemoryStore database upon network factory reset.

Bug:128499160
Test: manual
Test: atest FrameworksNetTests NetworkStackTests
Merged-In: I13ad04454e638905b74dd42a1c83266c7c37652f
Merged-In: Ia13ff10a57c2043f6676976f23ecfb2d2a9a6ef0
(cherry picked from commit ef6ef68c48b869aa9960edd81c73f3d31391ae26)

Change-Id: I42507451d55a620c0e2d271c895ad158f348c1a5

tests/net/java/android/net/IpMemoryStoreTest.java

@@ -321,4 +321,11 @@ public class IpMemoryStoreTest {
                 eq(TEST_OTHER_DATA_NAME), any());
         assertEquals(TEST_NETWORK_ATTRIBUTES, new NetworkAttributes(mNapCaptor.getValue()));
     }
+
+    @Test
+    public void testFactoryReset() throws RemoteException {
+        startIpMemoryStore(true /* supplyService */);
+        mStore.factoryReset();
+        verify(mMockService, times(1)).factoryReset();
+    }
 }