Added a flow control blocked notification message.

net/spdy/spdy_framer.cc

Index: net/spdy/spdy_framer.cc
diff --git a/net/spdy/spdy_framer.cc b/net/spdy/spdy_framer.cc
index 73af4bdf5b800638e85e6629993a0a17782feab8..53f911da3bc457a21c986e710ca117d2fea7de0b 100644
--- a/net/spdy/spdy_framer.cc
+++ b/net/spdy/spdy_framer.cc
@@ -1882,6 +1882,11 @@ SpdySerializedFrame* SpdyFramer::SerializeSettings(
   return builder.take();
 }
 
+SpdyFrame* SpdyFramer::CreateBlocked(SpdyStreamId stream_id) {
+  SpdyBlockedIR blocked_ir(stream_id);
+  return SerializeBlocked(blocked_ir);
+}
+
 SpdyFrame* SpdyFramer::SerializeBlocked(const SpdyBlockedIR& blocked) const {
   DCHECK_LE(4, protocol_version());
   SpdyFrameBuilder builder(GetBlockedSize());