[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 67cf0650691bc5fce518e2c2c1b06fac32c3baf9..f143607307b0a0dd3948fd5ad96c827d477f378d 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();
@@ -444,7 +444,7 @@ 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;