diff --git a/webrtc/test/fake_network_pipe_unittest.cc b/webrtc/test/fake_network_pipe_unittest.cc
index d429fce989..b10f297580 100644
--- a/webrtc/test/fake_network_pipe_unittest.cc
+++ b/webrtc/test/fake_network_pipe_unittest.cc
@@ -41,6 +41,8 @@ class FakeNetworkPipeTest : public ::testing::Test {
   virtual void SetUp() {
     TickTime::UseFakeClock(12345);
     receiver_.reset(new MockReceiver());
+    ON_CALL(*receiver_, DeliverPacket(_, _))
+        .WillByDefault(Return(PacketReceiver::DELIVERY_OK));
   }
 
   virtual void TearDown() {