Support HTTP/2 drafts 14 and 15 simultaneously.

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 5430e27ff47869d8190c080c3b19f2aeaa07d1c5..90bc6d00392f5f231d34245ee72da57a72343951 100644
--- a/net/spdy/spdy_session.cc
+++ b/net/spdy/spdy_session.cc
@@ -721,7 +721,8 @@ void SpdySession::InitializeWithSocket(
   DCHECK_GE(protocol_, kProtoSPDYMinimumVersion);
   DCHECK_LE(protocol_, kProtoSPDYMaximumVersion);
 
-  if (protocol_ == kProtoSPDY4)
+  if ((protocol_ >= kProtoSPDY4MinimumVersion) &&
+      (protocol_ <= kProtoSPDY4MaximumVersion))
     send_connection_header_prefix_ = true;
 
   if (protocol_ >= kProtoSPDY31) {
@@ -2457,8 +2458,8 @@ void SpdySession::OnPing(SpdyPingId unique_id, bool is_ack) {
       base::Bind(&NetLogSpdyPingCallback, unique_id, is_ack, "received"));
 
   // Send response to a PING from server.
-  if ((protocol_ >= kProtoSPDY4 && !is_ack) ||
-      (protocol_ < kProtoSPDY4 && unique_id % 2 == 0)) {
+  if ((protocol_ >= kProtoSPDY4MinimumVersion && !is_ack) ||
+      (protocol_ < kProtoSPDY4MinimumVersion && unique_id % 2 == 0)) {
     WritePingFrame(unique_id, true);
     return;
   }
@@ -2744,7 +2745,8 @@ void SpdySession::SendInitialData() {
   DCHECK(enable_sending_initial_data_);
 
   if (send_connection_header_prefix_) {
-    DCHECK_EQ(protocol_, kProtoSPDY4);
+    DCHECK_GE(protocol_, kProtoSPDY4MinimumVersion);
+    DCHECK_LE(protocol_, kProtoSPDY4MaximumVersion);
     scoped_ptr<SpdyFrame> connection_header_prefix_frame(
         new SpdyFrame(const_cast<char*>(kHttp2ConnectionHeaderPrefix),
                       kHttp2ConnectionHeaderPrefixSize,