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

ceee/ie/broker/api_dispatcher.h

Index: ceee/ie/broker/api_dispatcher.h
diff --git a/ceee/ie/broker/api_dispatcher.h b/ceee/ie/broker/api_dispatcher.h
index 6f6a86aebd560d5fe07a12632e2a649a060b1eb0..ce51dfbc0110eab2a47eb75a9035d9e2e572c2b8 100644
--- a/ceee/ie/broker/api_dispatcher.h
+++ b/ceee/ie/broker/api_dispatcher.h
@@ -307,8 +307,10 @@ ApiDispatcher::Invocation* NewApiInvocation() {
 
 // A singleton that initializes and keeps the ApiDispatcher used by production
 // code.
-class ProductionApiDispatcher : public ApiDispatcher,
-    public Singleton<ProductionApiDispatcher> {
+class ProductionApiDispatcher : public ApiDispatcher {
+ public:
+  static ProductionApiDispatcher* GetInstance();
+
  private:
   // This ensures no construction is possible outside of the class itself.
   friend struct DefaultSingletonTraits<ProductionApiDispatcher>;