CHECK to make sure connection_group is never empty.

net/socket/client_socket_handle.cc

 // Copyright (c) 2006-2008 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/socket/client_socket_handle.h"
 
 #include "base/compiler_specific.h"
 #include "base/logging.h"
 #include "net/base/net_errors.h"
 #include "net/socket/client_socket.h"
 #include "net/socket/client_socket_pool.h"
 
 namespace net {
 
 ClientSocketHandle::ClientSocketHandle(ClientSocketPool* pool)
     : pool_(pool),
       socket_(NULL),
       is_reused_(false),
       ALLOW_THIS_IN_INITIALIZER_LIST(
           callback_(this, &ClientSocketHandle::OnIOComplete)) {}
 
 ClientSocketHandle::~ClientSocketHandle() {
   Reset();
 }
 
 int ClientSocketHandle::Init(const std::string& group_name,
                              const HostResolver::RequestInfo& resolve_info,
                              int priority,
                              CompletionCallback* callback) {
+  CHECK(!group_name.empty());
   ResetInternal(true);
   group_name_ = group_name;
   int rv = pool_->RequestSocket(
       group_name, resolve_info, priority, this, &callback_);
   if (rv == ERR_IO_PENDING) {
     user_callback_ = callback;
   } else {
     HandleInitCompletion(rv);
   }
   return rv;
@@ skipping 33 matching lines @@
   callback->Run(result);
 }
 
 void ClientSocketHandle::HandleInitCompletion(int result) {
   CHECK(ERR_IO_PENDING != result);
   if (result != OK)
     ResetInternal(false);  // The request failed, so there's nothing to cancel.
 }
 
 }  // namespace net