Fix bug where QUIC_VERSION_21 would stall after sending too many headers.

net/quic/quic_session_test.cc

 // Copyright (c) 2012 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/quic/quic_session.h"
 
 #include <set>
 #include <vector>
 
 #include "base/basictypes.h"
@@ skipping 887 matching lines @@
   session_.OnSuccessfulVersionNegotiation(QUIC_VERSION_18);
   EXPECT_FALSE(session_.flow_controller()->IsEnabled());
   EXPECT_TRUE(stream->flow_controller()->IsEnabled());
 
   // Version 16 means all flow control is disabled.
   session_.OnSuccessfulVersionNegotiation(QUIC_VERSION_16);
   EXPECT_FALSE(session_.flow_controller()->IsEnabled());
   EXPECT_FALSE(stream->flow_controller()->IsEnabled());
 }
 
+TEST_P(QuicSessionTest, WindowUpdateUnblocksHeadersStream) {
+  // Test that a flow control blocked headers stream gets unblocked on recipt of
+  // a WINDOW_UPDATE frame. Regression test for b/17413860.
+  if (version() < QUIC_VERSION_21) {
+    return;
+  }
+
+  // Set the headers stream to be flow control blocked.
+  QuicHeadersStream* headers_stream =
+      QuicSessionPeer::GetHeadersStream(&session_);
+  QuicFlowControllerPeer::SetSendWindowOffset(headers_stream->flow_controller(),
+                                              0);
+  EXPECT_TRUE(headers_stream->flow_controller()->IsBlocked());
+
+  // Unblock the headers stream by supplying a WINDOW_UPDATE.
+  QuicWindowUpdateFrame window_update_frame(headers_stream->id(),
+                                            2 * kDefaultFlowControlSendWindow);
+  vector<QuicWindowUpdateFrame> frames;
+  frames.push_back(window_update_frame);
+  session_.OnWindowUpdateFrames(frames);
+  EXPECT_FALSE(headers_stream->flow_controller()->IsBlocked());
+}
+
 TEST_P(QuicSessionTest, TooManyUnfinishedStreamsCauseConnectionClose) {
   if (version() < QUIC_VERSION_18) {
     return;
   }
   // If a buggy/malicious peer creates too many streams that are not ended with
   // a FIN or RST then we send a connection close.
   ValueRestore<bool> old_flag(&FLAGS_close_quic_connection_unfinished_streams,
                               true);
 
   EXPECT_CALL(*connection_,
@@ skipping 12 matching lines @@
     frames.push_back(data1);
     session_.OnStreamFrames(frames);
     EXPECT_EQ(1u, session_.GetNumOpenStreams());
     session_.CloseStream(i);
   }
 }
 
 }  // namespace
 }  // namespace test
 }  // namespace net