Add metrics to track HTTP/0.9 usage for main frames and subresources

net/http/http_response_info.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "net/http/http_response_info.h"
 
 #include "base/logging.h"
 #include "base/pickle.h"
 #include "base/time/time.h"
 #include "net/base/auth.h"
@@ skipping 418 matching lines @@
     // Since ConnectionInfo is persisted to disk, deprecated values have to be
     // handled. Note that h2-14 and h2-15 are essentially wire compatible with
     // h2.
     // Intentional fallthrough.
     case CONNECTION_INFO_HTTP2_14:
     case CONNECTION_INFO_HTTP2_15:
     case CONNECTION_INFO_HTTP2:
       return "h2";
     case CONNECTION_INFO_QUIC1_SPDY3:
       return "quic/1+spdy/3";
+    case CONNECTION_INFO_HTTP0_9:
+      return "http/0.9";
     case NUM_OF_CONNECTION_INFOS:
       break;
   }
   NOTREACHED();
   return "";
 }
 
 }  // namespace net