Gather metrics classifying the cause of the TLS fallback.

net/socket/client_socket_handle.h

Index: net/socket/client_socket_handle.h
diff --git a/net/socket/client_socket_handle.h b/net/socket/client_socket_handle.h
index 58cf4ca6709b8d72c9fb86193142cd25d8409fc2..ab127fee24b9aa81c796755609fdc4cba1db672d 100644
--- a/net/socket/client_socket_handle.h
+++ b/net/socket/client_socket_handle.h
@@ -23,6 +23,7 @@
 #include "net/socket/client_socket_pool.h"
 #include "net/socket/connection_attempts.h"
 #include "net/socket/stream_socket.h"
+#include "net/ssl/ssl_failure_state.h"
 
 namespace net {
 
@@ -135,6 +136,9 @@ class NET_EXPORT ClientSocketHandle {
   void set_ssl_error_response_info(const HttpResponseInfo& ssl_error_state) {
     ssl_error_response_info_ = ssl_error_state;
   }
+  void set_ssl_failure_state(SSLFailureState ssl_failure_state) {
+    ssl_failure_state_ = ssl_failure_state;
+  }
   void set_pending_http_proxy_connection(ClientSocketHandle* connection) {
     pending_http_proxy_connection_.reset(connection);
   }
@@ -153,6 +157,7 @@ class NET_EXPORT ClientSocketHandle {
   const HttpResponseInfo& ssl_error_response_info() const {
     return ssl_error_response_info_;
   }
+  SSLFailureState ssl_failure_state() const { return ssl_failure_state_; }
   ClientSocketHandle* release_pending_http_proxy_connection() {
     return pending_http_proxy_connection_.release();
   }
@@ -207,6 +212,7 @@ class NET_EXPORT ClientSocketHandle {
   int pool_id_;  // See ClientSocketPool::ReleaseSocket() for an explanation.
   bool is_ssl_error_;
   HttpResponseInfo ssl_error_response_info_;
+  SSLFailureState ssl_failure_state_;
   scoped_ptr<ClientSocketHandle> pending_http_proxy_connection_;
   std::vector<ConnectionAttempt> connection_attempts_;
   base::TimeTicks init_time_;