Add chromeos namespace to the language options page and its friends.

chrome/browser/chromeos/dom_ui/language_hangul_options_handler.h

Index: chrome/browser/chromeos/dom_ui/language_hangul_options_handler.h
diff --git a/chrome/browser/chromeos/dom_ui/language_hangul_options_handler.h b/chrome/browser/chromeos/dom_ui/language_hangul_options_handler.h
index 5f132bceffba359d051081a417306c8455b4d18f..cedfb05f33936aa25a796613b2828191dead3b1b 100644
--- a/chrome/browser/chromeos/dom_ui/language_hangul_options_handler.h
+++ b/chrome/browser/chromeos/dom_ui/language_hangul_options_handler.h
@@ -11,6 +11,8 @@
 class DictionaryValue;
 class ListValue;
 
+namespace chromeos {
+
 // Hangul options page UI handler.
 class LanguageHangulOptionsHandler : public OptionsPageUIHandler {
  public:
@@ -27,4 +29,6 @@ class LanguageHangulOptionsHandler : public OptionsPageUIHandler {
   DISALLOW_COPY_AND_ASSIGN(LanguageHangulOptionsHandler);
 };
 
+}  // namespace chromeos
+
 #endif  // CHROME_BROWSER_CHROMEOS_DOM_UI_LANGUAGE_HANGUL_OPTIONS_HANDLER_H_