Switch some Singletons to use LeakySingleton.

base/i18n/number_formatting.cc

Index: base/i18n/number_formatting.cc
diff --git a/base/i18n/number_formatting.cc b/base/i18n/number_formatting.cc
index 7a69294a76fc547b8f7ef0b7b93e1234fc27a589..2ebb06bfdcc64d8ce3a1514cfac8531dc0b5175e 100644
--- a/base/i18n/number_formatting.cc
+++ b/base/i18n/number_formatting.cc
@@ -24,10 +24,9 @@ struct NumberFormatSingletonTraits
     DCHECK(U_SUCCESS(status));
     return formatter;
   }
-  // There's no ICU call to destroy a NumberFormat object other than
-  // operator delete, so use the default Delete, which calls operator delete.
-  // This can cause problems if a different allocator is used by this file than
-  // by ICU.
+
+  // Don't bother to delete.
+  static const bool kRegisterAtExit = false;
 };
 
 }  // namespace