diff --git a/quic/test_tools/quic_flow_controller_peer.cc b/quic/test_tools/quic_flow_controller_peer.cc
new file mode 100644
index 0000000..32efe45
--- /dev/null
+++ b/quic/test_tools/quic_flow_controller_peer.cc
@@ -0,0 +1,68 @@
+// Copyright 2014 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "net/third_party/quiche/src/quic/test_tools/quic_flow_controller_peer.h"
+
+#include <list>
+
+#include "net/third_party/quiche/src/quic/core/quic_flow_controller.h"
+#include "net/third_party/quiche/src/quic/core/quic_packets.h"
+
+namespace quic {
+namespace test {
+
+// static
+void QuicFlowControllerPeer::SetSendWindowOffset(
+    QuicFlowController* flow_controller,
+    QuicStreamOffset offset) {
+  flow_controller->send_window_offset_ = offset;
+}
+
+// static
+void QuicFlowControllerPeer::SetReceiveWindowOffset(
+    QuicFlowController* flow_controller,
+    QuicStreamOffset offset) {
+  flow_controller->receive_window_offset_ = offset;
+}
+
+// static
+void QuicFlowControllerPeer::SetMaxReceiveWindow(
+    QuicFlowController* flow_controller,
+    QuicByteCount window_size) {
+  flow_controller->receive_window_size_ = window_size;
+}
+
+// static
+QuicStreamOffset QuicFlowControllerPeer::SendWindowOffset(
+    QuicFlowController* flow_controller) {
+  return flow_controller->send_window_offset_;
+}
+
+// static
+QuicByteCount QuicFlowControllerPeer::SendWindowSize(
+    QuicFlowController* flow_controller) {
+  return flow_controller->SendWindowSize();
+}
+
+// static
+QuicStreamOffset QuicFlowControllerPeer::ReceiveWindowOffset(
+    QuicFlowController* flow_controller) {
+  return flow_controller->receive_window_offset_;
+}
+
+// static
+QuicByteCount QuicFlowControllerPeer::ReceiveWindowSize(
+    QuicFlowController* flow_controller) {
+  return flow_controller->receive_window_offset_ -
+         flow_controller->highest_received_byte_offset_;
+}
+
+// static
+QuicByteCount QuicFlowControllerPeer::WindowUpdateThreshold(
+    QuicFlowController* flow_controller) {
+  return flow_controller->WindowUpdateThreshold();
+}
+
+}  // namespace test
+}  // namespace quic