Add a new GetInstance() method for singleton classes, take 2.

This is a small step towards making all singleton classes use the Singleton<T> pattern within their code and not expect the callers to know about it.

This CL includes all files except those under chrome/browser, chrome/net, chrome/service and third_party/WebKit (these will be done in future CLs).

Suggested files to focus for reviewers:
- joi@ for files under src/ceee
- tommi@ for files under src/chrome_frame
- maruel@ for the rest of the files.

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

Review URL: http://codereview.chromium.org/5581008

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@68577 0039d316-1c4b-4281-b951-d872f2087c98

3 files changed, 9 insertions, 4 deletions

diff --git a/gfx/gtk_native_view_id_manager.cc b/gfx/gtk_native_view_id_manager.cc
index 8d9334d..904f46b 100644
--- a/gfx/gtk_native_view_id_manager.cc
+++ b/gfx/gtk_native_view_id_manager.cc
@@ -41,6 +41,11 @@ GtkNativeViewManager::GtkNativeViewManager() {
 GtkNativeViewManager::~GtkNativeViewManager() {
 }
 
+// static
+GtkNativeViewManager* GtkNativeViewManager::GetInstance() {
+  return Singleton<GtkNativeViewManager>::get();
+}
+
 gfx::NativeViewId GtkNativeViewManager::GetIdForWidget(gfx::NativeView widget) {
   // This is just for unit tests:
   if (!widget)
diff --git a/gfx/gtk_native_view_id_manager.h b/gfx/gtk_native_view_id_manager.h
index 05cf0d7..e97a852 100644
--- a/gfx/gtk_native_view_id_manager.h
+++ b/gfx/gtk_native_view_id_manager.h
@@ -36,11 +36,11 @@ struct _GtkPreserveWindow;
 // pointers and observes the various signals from the widget for when an X
 // window is created, destroyed etc. Thus it provides a thread safe mapping
 // from NativeViewIds to the current XID for that widget.
-//
-// You get a reference to the global instance with:
-//   Singleton<GtkNativeViewManager>()
 class GtkNativeViewManager {
  public:
+  // Returns the singleton instance.
+  static GtkNativeViewManager* GetInstance();
+
   // Must be called from the UI thread:
   //
   // Return a NativeViewId for the given widget and attach to the various
diff --git a/gfx/native_widget_types_gtk.cc b/gfx/native_widget_types_gtk.cc
index 097af2b..ccf428c 100644
--- a/gfx/native_widget_types_gtk.cc
+++ b/gfx/native_widget_types_gtk.cc
@@ -9,7 +9,7 @@
 namespace gfx {
 
 NativeViewId IdFromNativeView(NativeView view) {
-  return Singleton<GtkNativeViewManager>()->GetIdForWidget(view);
+  return GtkNativeViewManager::GetInstance()->GetIdForWidget(view);
 }
 
 }  // namespace gfx