Rename all methods accessing Singleton<T> as GetInstance().

base/singleton.h

Index: base/singleton.h
diff --git a/base/singleton.h b/base/singleton.h
index 8435c430c49941d079cd4db649d3ec16e921edcc..8ef265d7ec267f31ccfde0b801cf1c6423869fb8 100644
--- a/base/singleton.h
+++ b/base/singleton.h
@@ -114,7 +114,6 @@ template <typename Type> intptr_t
 template <typename Type> base::subtle::Atomic32
     StaticMemorySingletonTraits<Type>::dead_ = 0;
 
-
 // The Singleton<Type, Traits, DifferentiatingType> class manages a single
 // instance of Type which will be created on first use and will be destroyed at
 // normal process exit). The Trait::Delete function will not be called on
@@ -179,7 +178,11 @@ template <typename Type,
           typename Traits = DefaultSingletonTraits<Type>,
           typename DifferentiatingType = Type>
 class Singleton {
- public:
+ private:
+  // Classes using the Singleton<T> pattern should declare a GetInstance()
+  // method and call Singleton::get() from within that.
+  friend Type* Type::GetInstance();
+
   // This class is safe to be constructed and copy-constructed since it has no
   // member.