Make members of Singleton<T> private and only visible to the singleton type.

chrome/common/time_format.cc

Index: chrome/common/time_format.cc
diff --git a/chrome/common/time_format.cc b/chrome/common/time_format.cc
index c62f4f58e937f31d00ef34cde8da632b5be8bfd1..9de3a402302d947e5271e1705309694ba116c337 100644
--- a/chrome/common/time_format.cc
+++ b/chrome/common/time_format.cc
@@ -7,9 +7,9 @@
 #include <vector>
 
 #include "app/l10n_util.h"
+#include "base/lazy_instance.h"
 #include "base/logging.h"
 #include "base/scoped_ptr.h"
-#include "base/singleton.h"
 #include "base/stl_util-inl.h"
 #include "base/string16.h"
 #include "base/time.h"
@@ -168,8 +168,7 @@ class TimeFormatter {
       STLDeleteContainerPointers(time_elapsed_formatter_.begin(),
                                  time_elapsed_formatter_.end());
     }
-    friend class Singleton<TimeFormatter>;
-    friend struct DefaultSingletonTraits<TimeFormatter>;
+    friend struct base::DefaultLazyInstanceTraits<TimeFormatter>;
 
     std::vector<icu::PluralFormat*> short_formatter_;
     std::vector<icu::PluralFormat*> time_left_formatter_;
@@ -182,6 +181,9 @@ class TimeFormatter {
     DISALLOW_COPY_AND_ASSIGN(TimeFormatter);
 };
 
+static base::LazyInstance<TimeFormatter> g_time_formatter(
+    base::LINKER_INITIALIZED);
+
 void TimeFormatter::BuildFormats(
     FormatType format_type, std::vector<icu::PluralFormat*>* time_formats) {
   static const icu::UnicodeString kKeywords[] = {
@@ -253,8 +255,6 @@ icu::PluralFormat* TimeFormatter::createFallbackFormat(
   return format;
 }
 
-Singleton<TimeFormatter> time_formatter;
-
 static string16 FormatTimeImpl(const TimeDelta& delta, FormatType format_type) {
   if (delta.ToInternalValue() < 0) {
     NOTREACHED() << "Negative duration";
@@ -264,7 +264,7 @@ static string16 FormatTimeImpl(const TimeDelta& delta, FormatType format_type) {
   int number;
 
   const std::vector<icu::PluralFormat*>& formatters =
-    time_formatter->formatter(format_type);
+    g_time_formatter.Get().formatter(format_type);
 
   UErrorCode error = U_ZERO_ERROR;
   icu::UnicodeString time_string;