Account for HTTP/2 padding in receive windows.

net/quic/quic_headers_stream.cc

Index: net/quic/quic_headers_stream.cc
diff --git a/net/quic/quic_headers_stream.cc b/net/quic/quic_headers_stream.cc
index 435267b7d67e7c76524bb80e14c8e055faf0b9f3..48fb3a01c098d3f2a475a6bed39720e323c60adc 100644
--- a/net/quic/quic_headers_stream.cc
+++ b/net/quic/quic_headers_stream.cc
@@ -92,6 +92,10 @@ class QuicHeadersStream::SpdyFramerVisitor
     CloseConnection("SPDY DATA frame received.");
   }
 
+  void OnStreamPadding(SpdyStreamId stream_id, size_t len) override {
+    CloseConnection("SPDY frame padding received.");
+  }
+
   void OnError(SpdyFramer* framer) override {
     CloseConnection(base::StringPrintf(
         "SPDY framing error: %s",