Cleanup and simplify HostConfig and JsonHostConfig.

remoting/host/in_memory_host_config.cc

 // Copyright (c) 2011 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 "remoting/host/in_memory_host_config.h"
 
+#include "base/logging.h"
 #include "base/values.h"
 
 namespace remoting {
 
 InMemoryHostConfig::InMemoryHostConfig()
     : values_(new DictionaryValue()) {
 }
 
 InMemoryHostConfig::~InMemoryHostConfig() {}
 
 bool InMemoryHostConfig::GetString(const std::string& path,
-                                   std::string* out_value) {
-  base::AutoLock auto_lock(lock_);
+                                   std::string* out_value) const {
+  DCHECK(CalledOnValidThread());
   return values_->GetString(path, out_value);
 }
 
-bool InMemoryHostConfig::GetBoolean(const std::string& path, bool* out_value) {
-  base::AutoLock auto_lock(lock_);
+bool InMemoryHostConfig::GetBoolean(const std::string& path,
+                                    bool* out_value) const {
+  DCHECK(CalledOnValidThread());
   return values_->GetBoolean(path, out_value);
 }
 
-void InMemoryHostConfig::Save() {
-  // Save is NOP for in-memory host config.
+bool InMemoryHostConfig::Save() {
+  // Saving in-memory host config is not supported.
+  NOTREACHED();
+  return false;
 }
 
 void InMemoryHostConfig::SetString(const std::string& path,
                                    const std::string& in_value) {
-  base::AutoLock auto_lock(lock_);
+  DCHECK(CalledOnValidThread());
   values_->SetString(path, in_value);
 }
 
 void InMemoryHostConfig::SetBoolean(const std::string& path, bool in_value) {
-  base::AutoLock auto_lock(lock_);
+  DCHECK(CalledOnValidThread());
   values_->SetBoolean(path, in_value);
 }
 
 }  // namespace remoting