Add a new GetInstance() method for remaining files with singleton classes under chrome/browser.

chrome/browser/ui/cocoa/accelerators_cocoa.mm

Index: chrome/browser/ui/cocoa/accelerators_cocoa.mm
diff --git a/chrome/browser/ui/cocoa/accelerators_cocoa.mm b/chrome/browser/ui/cocoa/accelerators_cocoa.mm
index eba188897175efe388e1f40c1bb651153e3c4228..6f28a0ffdd8f2aa71204cfbbd81bb023111ab57c 100644
--- a/chrome/browser/ui/cocoa/accelerators_cocoa.mm
+++ b/chrome/browser/ui/cocoa/accelerators_cocoa.mm
@@ -6,6 +6,7 @@
 
 #import <Cocoa/Cocoa.h>
 
+#include "base/singleton.h"
 #include "chrome/app/chrome_command_ids.h"
 
 namespace {
@@ -48,6 +49,11 @@ AcceleratorsCocoa::AcceleratorsCocoa() {
   }
 }
 
+// static
+AcceleratorsCocoa* AcceleratorsCocoa::GetInstance() {
+  return Singleton<AcceleratorsCocoa>::get();
+}
+
 const menus::AcceleratorCocoa* AcceleratorsCocoa::GetAcceleratorForCommand(
     int command_id) {
   AcceleratorCocoaMap::iterator it = accelerators_.find(command_id);