Remove SPDY/2 code.

net/http/http_response_info.cc

Index: net/http/http_response_info.cc
diff --git a/net/http/http_response_info.cc b/net/http/http_response_info.cc
index 4c152103d2c15ed9741d7646bc3636c5211028c0..b97a0c3e817589fe13bfbbe407f6f1ba91c165b5 100644
--- a/net/http/http_response_info.cc
+++ b/net/http/http_response_info.cc
@@ -389,8 +389,6 @@ void HttpResponseInfo::Persist(base::Pickle* pickle,
 HttpResponseInfo::ConnectionInfo HttpResponseInfo::ConnectionInfoFromNextProto(
     NextProto next_proto) {
   switch (next_proto) {
-    case kProtoDeprecatedSPDY2:
-      return CONNECTION_INFO_DEPRECATED_SPDY2;
     case kProtoSPDY3:
     case kProtoSPDY31:
       return CONNECTION_INFO_SPDY3;
@@ -417,7 +415,8 @@ std::string HttpResponseInfo::ConnectionInfoToString(
     case CONNECTION_INFO_HTTP1:
       return "http/1";
     case CONNECTION_INFO_DEPRECATED_SPDY2:
-      return "spdy/2";
+      NOTREACHED();
+      return "";

[Ryan Hamilton, 2016/01/07 22:09:15]

Can we nuke this old value, or is it persisted somewhere?

[Bence, 2016/01/08 18:58:25]

Yes, we can nuke this.  However, in that case, I should probably reword the
comment above the enum:
https://code.google.com/p/chromium/codesearch#chromium/src/net/http/http_resp...

So how about a follow-up CL?

     case CONNECTION_INFO_SPDY3:
       return "spdy/3";
     // Since ConnectionInfo is persisted to disk, deprecated values have to be