use SkData oriented picture serialize api

blimp/test/support/compositor/picture_cache_test_support.cc

Index: blimp/test/support/compositor/picture_cache_test_support.cc
diff --git a/blimp/test/support/compositor/picture_cache_test_support.cc b/blimp/test/support/compositor/picture_cache_test_support.cc
index c58b941aeaa19bdf4eeeb7263eccfd939352b306..13cce4447071c29e56fe40eb896f5bfd27b6a14a 100644
--- a/blimp/test/support/compositor/picture_cache_test_support.cc
+++ b/blimp/test/support/compositor/picture_cache_test_support.cc
@@ -13,7 +13,6 @@
 #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"
@@ -30,10 +29,9 @@ sk_sp<const SkPicture> CreateSkPicture(SkColor color) {
 }
 
 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) {
@@ -42,8 +40,7 @@ BlobId GetBlobId(sk_sp<const SkPicture> picture) {
 }
 
 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,