Removing QUIC's VERSION_6, now that QUIC no longer needs to support the

net/quic/quic_protocol.cc

Index: net/quic/quic_protocol.cc
===================================================================
--- net/quic/quic_protocol.cc	(revision 217052)
+++ net/quic/quic_protocol.cc	(working copy)
@@ -123,10 +123,12 @@
 
 QuicVersion QuicVersionMax() { return kSupportedQuicVersions[0]; }
 
+QuicVersion QuicVersionMin() {
+  return kSupportedQuicVersions[arraysize(kSupportedQuicVersions) - 1];
+}
+
 QuicTag QuicVersionToQuicTag(const QuicVersion version) {
   switch (version) {
-    case QUIC_VERSION_6:
-      return MakeQuicTag('Q', '0', '0', '6');
     case QUIC_VERSION_7:
       return MakeQuicTag('Q', '0', '0', '7');
     case QUIC_VERSION_8:
@@ -140,13 +142,10 @@
 }
 
 QuicVersion QuicTagToQuicVersion(const QuicTag version_tag) {
-  const QuicTag quic_tag_v6 = MakeQuicTag('Q', '0', '0', '6');
   const QuicTag quic_tag_v7 = MakeQuicTag('Q', '0', '0', '7');
   const QuicTag quic_tag_v8 = MakeQuicTag('Q', '0', '0', '8');
 
-  if (version_tag == quic_tag_v6) {
-    return QUIC_VERSION_6;
-  } else if (version_tag == quic_tag_v7) {
+  if (version_tag == quic_tag_v7) {
     return QUIC_VERSION_7;
   } else if (version_tag == quic_tag_v8) {
     return QUIC_VERSION_8;
@@ -164,7 +163,6 @@
 
 string QuicVersionToString(const QuicVersion version) {
   switch (version) {
-    RETURN_STRING_LITERAL(QUIC_VERSION_6);
     RETURN_STRING_LITERAL(QUIC_VERSION_7);
     RETURN_STRING_LITERAL(QUIC_VERSION_8);
     default: