Make members of Singleton<T> private and only visible to the singleton type. This enforces that the Singleton<T> pattern can only be used within classes which want singleton-ness.

As part of this CL I have also fixed up files which got missed in my previous CLs to use a GetInstance() method and use Singleton<T> from the source file.

There are a small number of places where I have also switched to LazyInstance as that was more appropriate for types used in a single source file.

BUG=65298
TEST=all existing tests should continue to pass.

Review URL: http://codereview.chromium.org/5682008

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@69107 0039d316-1c4b-4281-b951-d872f2087c98

2 files changed, 13 insertions, 9 deletions

diff --git a/printing/backend/print_backend_cups.cc b/printing/backend/print_backend_cups.cc
index 9fbf2ab..e75a800 100644
--- a/printing/backend/print_backend_cups.cc
+++ b/printing/backend/print_backend_cups.cc
@@ -12,9 +12,9 @@
 #include <pthread.h>
 
 #include "base/file_util.h"
+#include "base/lazy_instance.h"
 #include "base/lock.h"
 #include "base/logging.h"
-#include "base/singleton.h"
 #include "base/string_number_conversions.h"
 #include "base/values.h"
 #include "googleurl/src/gurl.h"
@@ -66,6 +66,9 @@ class GcryptInitializer {
   }
 };
 
+static base::LazyInstance<GcryptInitializer> g_gcrypt_initializer(
+    base::LINKER_INITIALIZED);
+
 }  // namespace
 #endif
 
@@ -188,7 +191,7 @@ scoped_refptr<PrintBackend> PrintBackend::CreateInstance(
     const DictionaryValue* print_backend_settings) {
 #if !defined(OS_MACOSX)
   // Initialize gcrypt library.
-  Singleton<GcryptInitializer>::get();
+  g_gcrypt_initializer.Get();
 #endif
 
   std::string print_server_url_str;
diff --git a/printing/printed_document.cc b/printing/printed_document.cc
index 75d4b95..0880da5 100644
--- a/printing/printed_document.cc
+++ b/printing/printed_document.cc
@@ -13,8 +13,8 @@
 #include "base/file_path.h"
 #include "base/file_util.h"
 #include "base/i18n/file_util_icu.h"
+#include "base/lazy_instance.h"
 #include "base/message_loop.h"
-#include "base/singleton.h"
 #include "base/string_util.h"
 #include "base/utf_string_conversions.h"
 #include "base/i18n/time_formatting.h"
@@ -37,7 +37,8 @@ struct PrintDebugDumpPath {
   FilePath debug_dump_path;
 };
 
-Singleton<PrintDebugDumpPath> g_debug_dump_info;
+static base::LazyInstance<PrintDebugDumpPath> g_debug_dump_info(
+    base::LINKER_INITIALIZED);
 
 }  // namespace
 
@@ -244,7 +245,7 @@ void PrintedDocument::PrintHeaderFooter(gfx::NativeDrawingContext context,
 }
 
 void PrintedDocument::DebugDump(const PrintedPage& page) {
-  if (!g_debug_dump_info->enabled)
+  if (!g_debug_dump_info.Get().enabled)
     return;
 
   string16 filename;
@@ -258,19 +259,19 @@ void PrintedDocument::DebugDump(const PrintedPage& page) {
   filename += ASCIIToUTF16("_.emf");
 #if defined(OS_WIN)
   page.native_metafile()->SaveTo(
-      g_debug_dump_info->debug_dump_path.Append(filename).ToWStringHack());
+      g_debug_dump_info.Get().debug_dump_path.Append(filename).ToWStringHack());
 #else  // OS_WIN
   NOTIMPLEMENTED();
 #endif  // OS_WIN
 }
 
 void PrintedDocument::set_debug_dump_path(const FilePath& debug_dump_path) {
-  g_debug_dump_info->enabled = !debug_dump_path.empty();
-  g_debug_dump_info->debug_dump_path = debug_dump_path;
+  g_debug_dump_info.Get().enabled = !debug_dump_path.empty();
+  g_debug_dump_info.Get().debug_dump_path = debug_dump_path;
 }
 
 const FilePath& PrintedDocument::debug_dump_path() {
-  return g_debug_dump_info->debug_dump_path;
+  return g_debug_dump_info.Get().debug_dump_path;
 }
 
 PrintedDocument::Mutable::Mutable(PrintedPagesSource* source)