use SkData oriented picture serialize api

blimp/test/support/compositor/picture_cache_test_support.cc

 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "blimp/test/support/compositor/picture_cache_test_support.h"
 
 #include "base/memory/ptr_util.h"
 #include "blimp/common/blob_cache/blob_cache.h"
 #include "blimp/common/blob_cache/id_util.h"
 #include "third_party/skia/include/core/SkCanvas.h"
 #include "third_party/skia/include/core/SkColor.h"
 #include "third_party/skia/include/core/SkData.h"
 #include "third_party/skia/include/core/SkPicture.h"
 #include "third_party/skia/include/core/SkPictureRecorder.h"
 #include "third_party/skia/include/core/SkRefCnt.h"
-#include "third_party/skia/include/core/SkStream.h"
 #include "ui/gfx/geometry/point_f.h"
 #include "ui/gfx/geometry/rect.h"
 #include "ui/gfx/geometry/rect_f.h"
 #include "ui/gfx/skia_util.h"
 
 namespace blimp {
 
 sk_sp<const SkPicture> CreateSkPicture(SkColor color) {
   SkPictureRecorder recorder;
   sk_sp<SkCanvas> canvas =
       sk_ref_sp(recorder.beginRecording(SkRect::MakeWH(1, 1)));
   canvas->drawColor(color);
   return recorder.finishRecordingAsPicture();
 }
 
 sk_sp<SkData> SerializePicture(sk_sp<const SkPicture> picture) {
-  SkDynamicMemoryWStream stream;
-  picture->serialize(&stream, nullptr);
-  DCHECK(stream.bytesWritten());
-  return sk_sp<SkData>(stream.copyToData());
+  sk_sp<SkData> data = picture->serialize();
+  DCHECK(data->size());

[Wez, 2016/09/16 16:34:02]

nit: I realise this was already in this state, but can we make this consistent
with the other blimp call-site and use DCHECK_GT(...)?

[reed1, 2016/09/16 20:06:29]

That seems related to the other question about zero-length serialization. Is it
a contract of the caller that the picture is never empty?

[Wez, 2016/09/17 01:50:03]

No, my point here was simply to be consistent in using DCHECK_GE(foo, 0) versus
DCHECK(foo).

+  return data;
 }
 
 BlobId GetBlobId(sk_sp<const SkPicture> picture) {
   sk_sp<SkData> data = SerializePicture(picture);
   return CalculateBlobId(data->data(), data->size());
 }
 
 sk_sp<const SkPicture> DeserializePicture(sk_sp<SkData> data) {
-  SkMemoryStream stream(data);
-  return SkPicture::MakeFromStream(&stream, nullptr);
+  return SkPicture::MakeFromData(data.get());
 }
 
 bool PicturesEqual(sk_sp<const SkPicture> picture,
                    const cc::PictureData& picture_data) {
   if (picture->uniqueID() != picture_data.unique_id) {
     return false;
   }
   sk_sp<const SkPicture> deserialized_picture =
       DeserializePicture(picture_data.data);
   return GetBlobId(picture) == GetBlobId(deserialized_picture);
 }
 
 cc::PictureData CreatePictureData(sk_sp<const SkPicture> picture) {
   return cc::PictureData(picture->uniqueID(), SerializePicture(picture));
 }
 
 }  // namespace blimp