Update from https://crrev.com/304121

net/socket/next_proto.h

Index: net/socket/next_proto.h
diff --git a/net/socket/next_proto.h b/net/socket/next_proto.h
index 465001d4b5b749a0eefccadf907ee99e556c60f8..c12a45bcfde9cae8b9c0068a7b14b91838b14dbd 100644
--- a/net/socket/next_proto.h
+++ b/net/socket/next_proto.h
@@ -25,11 +25,14 @@ enum NextProto {
 
   kProtoDeprecatedSPDY2 = 100,
   kProtoSPDYMinimumVersion = kProtoDeprecatedSPDY2,
+  kProtoSPDYHistogramOffset = kProtoDeprecatedSPDY2,
   kProtoSPDY3 = 101,
   kProtoSPDY31 = 102,
-  // HTTP/2 draft-14 was 103,
-  kProtoSPDY4 = 104,  // SPDY4 is HTTP/2 draft-15.
-  kProtoSPDYMaximumVersion = kProtoSPDY4,
+  kProtoSPDY4_14 = 103,  // HTTP/2 draft-14
+  kProtoSPDY4MinimumVersion = kProtoSPDY4_14,
+  kProtoSPDY4_15 = 104,  // HTTP/2 draft-15
+  kProtoSPDY4MaximumVersion = kProtoSPDY4_15,
+  kProtoSPDYMaximumVersion = kProtoSPDY4MaximumVersion,
 
   kProtoQUIC1SPDY3 = 200,
 
@@ -51,9 +54,7 @@ NET_EXPORT NextProtoVector NextProtosWithSpdyAndQuic(bool spdy_enabled,
                                                      bool quic_enabled);
 
 // All of these also enable QUIC.
-NET_EXPORT NextProtoVector NextProtosSpdy3();
 NET_EXPORT NextProtoVector NextProtosSpdy31();
-NET_EXPORT NextProtoVector NextProtosSpdy31WithSpdy2();
 NET_EXPORT NextProtoVector NextProtosSpdy4Http2();
 
 }  // namespace net