Account for HTTP/2 padding in receive windows.

net/spdy/spdy_session.cc

Index: net/spdy/spdy_session.cc
diff --git a/net/spdy/spdy_session.cc b/net/spdy/spdy_session.cc
index dcdc92813b88fc78215aac9b309f6be1df6479a5..1d73e1524540f5b7cd22fbe49960a99c14cadcc5 100644
--- a/net/spdy/spdy_session.cc
+++ b/net/spdy/spdy_session.cc
@@ -2055,9 +2055,20 @@ void SpdySession::OnStreamFrameData(SpdyStreamId stream_id,
   CHECK(in_io_loop_);
 
   if (data == NULL && len != 0) {
-    // This is notification of consumed data padding.
-    // TODO(jgraettinger): Properly flow padding into WINDOW_UPDATE frames.
-    // See crbug.com/353012.
+    if (flow_control_state_ != FLOW_CONTROL_STREAM_AND_SESSION)
+      return;
+
+    // Decrease window size because padding bytes are received.
+    // Increase window size because padding bytes are consumed (by discarding).
+    // Net result: |session_unacked_recv_window_bytes_| increases by |len|,
+    // |session_recv_window_size_| does not change.
+    DecreaseRecvWindowSize(static_cast<int32>(len));
+    IncreaseRecvWindowSize(static_cast<int32>(len));
+
+    ActiveStreamMap::iterator it = active_streams_.find(stream_id);
+    if (it == active_streams_.end())
+      return;
+    it->second.stream->OnPaddingConsumed(len);
     return;
   }