remove SkDataSet, and just store a key/value in SkAnnotation

include/core/SkAnnotation.h

 /*
  * Copyright 2012 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #ifndef SkAnnotation_DEFINED
 #define SkAnnotation_DEFINED
 
 #include "SkFlattenable.h"
+#include "SkString.h"
 
 class SkData;
-class SkDataSet;
 class SkStream;
 class SkWStream;
 struct SkPoint;
 
 /**
  *  Experimental class for annotating draws. Do not use directly yet.
  *  Use helper functions at the bottom of this file for now.
  */
 class SkAnnotation : public SkFlattenable {
 public:
     enum Flags {
         // If set, the associated drawing primitive should not be drawn
         kNoDraw_Flag  = 1 << 0,
     };
 
-    SkAnnotation(SkDataSet*, uint32_t flags);
+    SkAnnotation(const char key[], SkData* value, uint32_t flags);
     virtual ~SkAnnotation();
 
     uint32_t getFlags() const { return fFlags; }
-    SkDataSet* getDataSet() const { return fDataSet; }
 
     bool isNoDraw() const { return SkToBool(fFlags & kNoDraw_Flag); }
 
     /**
-     *  Helper for search the annotation's dataset.
+     *  Return the data for the specified key, or NULL.
      */
-    SkData* find(const char name[]) const;
+    SkData* find(const char key[]) const;
 
     SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(SkAnnotation)
 
 protected:
     SkAnnotation(SkFlattenableReadBuffer&);
     virtual void flatten(SkFlattenableWriteBuffer&) const SK_OVERRIDE;
 
 private:
-    SkDataSet*  fDataSet;
+    SkString    fKey;
+    SkData*     fData;
     uint32_t    fFlags;
 
     void writeToStream(SkWStream*) const;
     void readFromStream(SkStream*);
 
     typedef SkFlattenable INHERITED;
 };
 
 /**
  *  Experimental collection of predefined Keys into the Annotation dictionary
@@ skipping 58 matching lines @@
  *
  *  If the backend of this canvas does not support annotations, this call is
  *  safely ignored.
  *
  *  The caller is responsible for managing its ownership of the SkData.
  */
 SK_API void SkAnnotateLinkToDestination(SkCanvas*, const SkRect&, SkData*);
 
 
 #endif