[skia] Update SkSerialProcs to use new type (flutter#179347)

This lets us eventually use the const SkData version added in
https://skia-review.googlesource.com/c/skia/+/1109339

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Author: kjlubick

engine/src/flutter/shell/common/rasterizer.cc

@@ -856,7 +856,7 @@ static sk_sp<SkData> ScreenshotLayerTreeAsPicture(
 #else
   SkSerialProcs procs = {0};
   procs.fTypefaceProc = SerializeTypefaceWithData;
-  procs.fImageProc = [](SkImage* img, void*) -> sk_sp<SkData> {
+  procs.fImageProc = [](SkImage* img, void*) -> SkSerialReturnType {
     return SkPngEncoder::Encode(nullptr, img, SkPngEncoder::Options{});
   };
 #endif

engine/src/flutter/shell/common/serialization_callbacks.cc

@@ -2,6 +2,7 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
+#include "flutter/shell/common/serialization_callbacks.h"
 #include "flutter/fml/logging.h"
 #include "third_party/skia/include/core/SkColorSpace.h"
 #include "third_party/skia/include/core/SkImage.h"
@@ -11,11 +12,12 @@
 
 namespace flutter {
 
-sk_sp<SkData> SerializeTypefaceWithoutData(SkTypeface* typeface, void* ctx) {
+SkSerialReturnType SerializeTypefaceWithoutData(SkTypeface* typeface,
+                                                void* ctx) {
   return SkData::MakeEmpty();
 }
 
-sk_sp<SkData> SerializeTypefaceWithData(SkTypeface* typeface, void* ctx) {
+SkSerialReturnType SerializeTypefaceWithData(SkTypeface* typeface, void* ctx) {
   return typeface->serialize(SkTypeface::SerializeBehavior::kDoIncludeData);
 }
 
@@ -33,7 +35,7 @@ struct ImageMetaData {
   bool has_color_space;
 } __attribute__((packed));
 
-sk_sp<SkData> SerializeImageWithoutData(SkImage* image, void* ctx) {
+SkSerialReturnType SerializeImageWithoutData(SkImage* image, void* ctx) {
   const auto& info = image->imageInfo();
   SkDynamicMemoryWStream stream;
 

engine/src/flutter/shell/common/serialization_callbacks.h

@@ -7,18 +7,20 @@
 
 #include "flutter/fml/logging.h"
 #include "third_party/skia/include/core/SkImage.h"
+#include "third_party/skia/include/core/SkSerialProcs.h"
 #include "third_party/skia/include/core/SkTypeface.h"
 
 namespace flutter {
 
-sk_sp<SkData> SerializeTypefaceWithoutData(SkTypeface* typeface, void* ctx);
-sk_sp<SkData> SerializeTypefaceWithData(SkTypeface* typeface, void* ctx);
+SkSerialReturnType SerializeTypefaceWithoutData(SkTypeface* typeface,
+                                                void* ctx);
+SkSerialReturnType SerializeTypefaceWithData(SkTypeface* typeface, void* ctx);
 sk_sp<SkTypeface> DeserializeTypefaceWithoutData(const void* data,
                                                  size_t length,
                                                  void* ctx);
 
 // Serializes only the metadata of the image and not the underlying pixel data.
-sk_sp<SkData> SerializeImageWithoutData(SkImage* image, void* ctx);
+SkSerialReturnType SerializeImageWithoutData(SkImage* image, void* ctx);
 sk_sp<SkImage> DeserializeImageWithoutData(const void* data,
                                            size_t length,
                                            void* ctx);