Refactor read and write buffers.

tests/FlatDataTest.cpp

Index: tests/FlatDataTest.cpp
diff --git a/tests/FlatDataTest.cpp b/tests/FlatDataTest.cpp
index 1f0e12a34ff509f9011963adfc2ad4060d17fd46..36fecf962504ed9ba64f512dc0d2e38a882142d1 100644
--- a/tests/FlatDataTest.cpp
+++ b/tests/FlatDataTest.cpp
@@ -17,12 +17,12 @@
 #include "Test.h"
 
 struct SkFlattenableTraits {
-    static void flatten(SkOrderedWriteBuffer& buffer, const SkFlattenable& flattenable) {
+    static void flatten(SkWriteBuffer& buffer, const SkFlattenable& flattenable) {
         buffer.writeFlattenable(&flattenable);
     }
 };
 struct SkBitmapTraits {
-    static void flatten(SkOrderedWriteBuffer& buffer, const SkBitmap& bitmap) {
+    static void flatten(SkWriteBuffer& buffer, const SkBitmap& bitmap) {
         bitmap.flatten(buffer);
     }
 };