Fix a few spelling errors in comments.

net/dns/dns_config_service_posix.h

 // 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.
 
 #ifndef NET_DNS_DNS_CONFIG_SERVICE_POSIX_H_
 #define NET_DNS_DNS_CONFIG_SERVICE_POSIX_H_
 
 #if !defined(OS_ANDROID)
 #include <sys/types.h>
 #include <netinet/in.h>
@@ skipping 53 matching lines @@
   void OnHostsChanged(bool succeeded);
 
   scoped_ptr<Watcher> watcher_;
   // Allow a mock hosts file for testing purposes.
   const base::FilePath::CharType* file_path_hosts_;
   // Allow a mock DNS server for testing purposes.
   const DnsConfig* dns_config_for_testing_;
   scoped_refptr<ConfigReader> config_reader_;
   scoped_refptr<HostsReader> hosts_reader_;
 #if defined(OS_ANDROID)
-  // Has DnsConfigWatcher detected any config chagnes yet?
+  // Has DnsConfigWatcher detected any config changes yet?
   bool seen_config_change_;
 #endif
 
   DISALLOW_COPY_AND_ASSIGN(DnsConfigServicePosix);
 };
 
 enum ConfigParsePosixResult {
   CONFIG_PARSE_POSIX_OK = 0,
   CONFIG_PARSE_POSIX_RES_INIT_FAILED,
   CONFIG_PARSE_POSIX_RES_INIT_UNSET,
@@ skipping 11 matching lines @@
 // Fills in |dns_config| from |res|.
 ConfigParsePosixResult NET_EXPORT_PRIVATE ConvertResStateToDnsConfig(
     const struct __res_state& res, DnsConfig* dns_config);
 #endif
 
 }  // namespace internal
 
 }  // namespace net
 
 #endif  // NET_DNS_DNS_CONFIG_SERVICE_POSIX_H_