Do not read redundant output param for StorePolicy DBus call family.

chromeos/dbus/session_manager_client.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 "chromeos/dbus/session_manager_client.h"
 
 #include <stddef.h>
 #include <stdint.h>
 
 #include <memory>
@@ skipping 718 matching lines @@
     callback.Run(std::string(), response_type);
 
     LogPolicyResponseUma(method_name, response_type);
   }
 
   // Called when kSessionManagerStorePolicy or kSessionManagerStorePolicyForUser
   // method is complete.
   void OnStorePolicy(const std::string& method_name,
                      const StorePolicyCallback& callback,
                      dbus::Response* response) {
-    bool success = false;
-    if (!response) {
-      LOG(ERROR) << "Failed to call " << method_name;
-    } else {
-      dbus::MessageReader reader(response);
-      if (!reader.PopBool(&success))
-        LOG(ERROR) << "Invalid response: " << response->ToString();
-    }
-    callback.Run(success);
+    LOG_IF(ERROR, !response) << "Failed to call " << method_name;
+    callback.Run(bool(response));

[Daniel Erat, 2017/05/18 16:32:27]

i think we usually avoid using c-style casts. would you be okay with changing
this to !!response or response != nullptr or something similar?

[hidehiko, 2017/05/18 16:54:27]

Good catch!
It is bool ctor, but can be interpreted as cast.
So, introduced a var and compared with nullptr explicitly,
so there's no ambiguity here, IMO. WDYT?

cf) https://google.github.io/styleguide/cppguide.html#Casting
So, alternatively bool{response} can be used.

   }
 
   // Called when the owner key set signal is received.
   void OwnerKeySetReceived(dbus::Signal* signal) {
     dbus::MessageReader reader(signal);
     std::string result_string;
     if (!reader.PopString(&result_string)) {
       LOG(ERROR) << "Invalid signal: " << signal->ToString();
       return;
     }
@@ skipping 404 matching lines @@
 
 SessionManagerClient* SessionManagerClient::Create(
     DBusClientImplementationType type) {
   if (type == REAL_DBUS_CLIENT_IMPLEMENTATION)
     return new SessionManagerClientImpl();
   DCHECK_EQ(FAKE_DBUS_CLIENT_IMPLEMENTATION, type);
   return new SessionManagerClientStubImpl();
 }
 
 }  // namespace chromeos