Add methods to SkLayerDrawLooper to allow adding layers on top

include/effects/SkLayerDrawLooper.h

 /*
  * Copyright 2011 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #ifndef SkLayerDrawLooper_DEFINED
 #define SkLayerDrawLooper_DEFINED
 
@@ skipping 81 matching lines @@
     /**
      *  This layer will draw with the original paint, at the specified offset
      */
     void addLayer(SkScalar dx, SkScalar dy);
 
     /**
      *  This layer will with the original paint and no offset.
      */
     void addLayer() { this->addLayer(0, 0); }
 
+    /// Similar to addLayer, but adds a layer to the top.
+    SkPaint* addLayerOnTop(const LayerInfo&);
+
     // overrides from SkDrawLooper
     virtual void init(SkCanvas*);
     virtual bool next(SkCanvas*, SkPaint* paint);
 
     SK_DEVELOPER_TO_STRING()
     SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(SkLayerDrawLooper)
 
 protected:
     SkLayerDrawLooper(SkFlattenableReadBuffer&);
     virtual void flatten(SkFlattenableWriteBuffer&) const SK_OVERRIDE;
 
 private:
     struct Rec {
         Rec*    fNext;
         SkPaint fPaint;
         LayerInfo fInfo;
-
-        static Rec* Reverse(Rec*);
     };
     Rec*    fRecs;
+    Rec*    fTopRec;
     int     fCount;
 
     // state-machine during the init/next cycle
     Rec* fCurrRec;
 
     static void ApplyInfo(SkPaint* dst, const SkPaint& src, const LayerInfo&);
 
     class MyRegistrar : public SkFlattenable::Registrar {
     public:
         MyRegistrar();
     };
 
     typedef SkDrawLooper INHERITED;
 };
 
 #endif