change pixelref to not inherit from SkFlattenable

include/core/SkMallocPixelRef.h

Index: include/core/SkMallocPixelRef.h
diff --git a/include/core/SkMallocPixelRef.h b/include/core/SkMallocPixelRef.h
index 2db81bb31b508f5370a1ae7b728bbb0e3731f198..5415e01900dbe46ebe2468513acf343d3c5f7cb0 100644
--- a/include/core/SkMallocPixelRef.h
+++ b/include/core/SkMallocPixelRef.h
@@ -82,18 +82,21 @@ public:
                                    SkColorTable*) SK_OVERRIDE;
     };
 
+#ifdef SK_SUPPORT_LEGACY_PIXELREF_UNFLATTENABLE
     SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(SkMallocPixelRef)
+#endif
 
 protected:
     // The ownPixels version of this constructor is deprecated.
     SkMallocPixelRef(const SkImageInfo&, void* addr, size_t rb, SkColorTable*,
                      bool ownPixels);
+#ifdef SK_SUPPORT_LEGACY_PIXELREF_UNFLATTENABLE
     SkMallocPixelRef(SkReadBuffer& buffer);
+#endif
     virtual ~SkMallocPixelRef();
 
     virtual bool onNewLockPixels(LockRec*) SK_OVERRIDE;
     virtual void onUnlockPixels() SK_OVERRIDE;
-    virtual void flatten(SkWriteBuffer&) const SK_OVERRIDE;
     virtual size_t getAllocatedSizeInBytes() const SK_OVERRIDE;
 
 private: