Cleanup: Pass std::string as const reference if possible

chromeos/dbus/fake_shill_manager_client.cc

 // Copyright 2013 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 "chromeos/dbus/fake_shill_manager_client.h"
 
 #include "base/bind.h"
 #include "base/command_line.h"
 #include "base/location.h"
 #include "base/message_loop/message_loop.h"
@@ skipping 1097 matching lines @@
       s_tdls_busy_count = 1;
     return true;
   } else if (arg0 == "roaming") {
     // "home", "roaming", or "required"
     roaming_state_ = arg1;
     return true;
   }
   return SetInitialNetworkState(arg0, arg1);
 }
 
-bool FakeShillManagerClient::SetInitialNetworkState(std::string type_arg,
-                                                    std::string state_arg) {
+bool FakeShillManagerClient::SetInitialNetworkState(
+    const std::string& type_arg,
+    const std::string& state_arg) {
   int state_arg_as_int = -1;
   base::StringToInt(state_arg, &state_arg_as_int);
 
   std::string state;
   if (state_arg.empty() || state_arg == "1" || state_arg == "on" ||
       state_arg == "enabled" || state_arg == "connected" ||
       state_arg == "online") {
     // Enabled and connected (default value)
     state = shill::kStateOnline;
   } else if (state_arg == "0" || state_arg == "off" ||
@@ skipping 80 matching lines @@
       LOG(WARNING) << "Invalid state: " << state << " for " << type;
       result = shill::kStateIdle;
     }
   }
   VLOG(1) << "Initial state for: " << type << " = " << result
           << " Enabled: " << *enabled;
   return result;
 }
 
 }  // namespace chromeos