Refactor read and write buffers.

include/core/SkUnitMapper.h

Index: include/core/SkUnitMapper.h
diff --git a/include/core/SkUnitMapper.h b/include/core/SkUnitMapper.h
index 57a8b8332e90051caad2f8342b297ccf9af035fd..46f6eddd709e0238b9b060d2ca6ae5da9ebe9025 100644
--- a/include/core/SkUnitMapper.h
+++ b/include/core/SkUnitMapper.h
@@ -28,7 +28,7 @@ public:
     SK_DEFINE_FLATTENABLE_TYPE(SkUnitMapper)
 
 protected:
-    SkUnitMapper(SkFlattenableReadBuffer& rb) : SkFlattenable(rb) {}
+    SkUnitMapper(SkReadBuffer& rb) : SkFlattenable(rb) {}
 
 private:
     typedef SkFlattenable INHERITED;