[SPDY] Incorporate latest framing changes from HTTP2 into SPDY 4 as SPDY 4a2.

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 515e5147684da232fdab23b726126e39aabc8b63..6669dcc85cf304e682b6d264bf47e0d21428a4bc 100644
--- a/net/spdy/spdy_session.cc
+++ b/net/spdy/spdy_session.cc
@@ -61,7 +61,7 @@ int NPNToSpdyVersion(NextProto next_proto) {
     case kProtoSPDY3:
     case kProtoSPDY31:
       return kSpdyVersion3;
-    case kProtoSPDY4a1:
+    case kProtoSPDY4a2:
       return kSpdyVersion4;
     default:
       NOTREACHED();
@@ -432,7 +432,7 @@ Error SpdySession::InitializeWithSocket(
   }
 
   DCHECK_GE(protocol, kProtoSPDY2);
-  DCHECK_LE(protocol, kProtoSPDY4a1);
+  DCHECK_LE(protocol, kProtoSPDY4a2);
   if (protocol >= kProtoSPDY31) {
     flow_control_state_ = FLOW_CONTROL_STREAM_AND_SESSION;
     session_send_window_size_ = kSpdySessionInitialWindowSize;