SkData can allocate room for its contents in the same block

src/core/SkFlattenableSerialization.cpp

Index: src/core/SkFlattenableSerialization.cpp
diff --git a/src/core/SkFlattenableSerialization.cpp b/src/core/SkFlattenableSerialization.cpp
index b33bca6dbbe47c9a0fb15ed71289abb1f943a035..31602079a39b995897d906c8996b726a92478b42 100644
--- a/src/core/SkFlattenableSerialization.cpp
+++ b/src/core/SkFlattenableSerialization.cpp
@@ -15,9 +15,9 @@ SkData* SkValidatingSerializeFlattenable(SkFlattenable* flattenable) {
     SkWriteBuffer writer(SkWriteBuffer::kValidation_Flag);
     writer.writeFlattenable(flattenable);
     size_t size = writer.bytesWritten();
-    void* data = sk_malloc_throw(size);
-    writer.writeToMemory(data);
-    return SkData::NewFromMalloc(data, size);
+    SkData* data = SkData::NewUninitialized(size);
+    writer.writeToMemory(data->writable_data());
+    return data;
 }
 
 SkFlattenable* SkValidatingDeserializeFlattenable(const void* data, size_t size,