use SkData oriented picture serialize api

blimp/engine/renderer/blimp_engine_picture_cache.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/engine/renderer/blimp_engine_picture_cache.h"
 
 #include "base/logging.h"
 #include "base/memory/ptr_util.h"
-#include "third_party/skia/include/core/SkStream.h"
 
 namespace blimp {
 namespace engine {
 
 BlimpEnginePictureCache::BlimpEnginePictureCache(
     SkPixelSerializer* pixel_serializer)
     : pixel_serializer_(pixel_serializer) {}
 
 BlimpEnginePictureCache::~BlimpEnginePictureCache() = default;
 
@@ skipping 25 matching lines @@
   }
 
   // All new items will be sent to the client, so clear everything.
   pictures_.clear();
   reference_tracker_.ClearRefCounts();
 
   return update;
 }
 
 void BlimpEnginePictureCache::Put(const SkPicture* picture) {
-  SkDynamicMemoryWStream stream;
-  picture->serialize(&stream, pixel_serializer_);
-  DCHECK_GE(stream.bytesWritten(), 0u);
+  sk_sp<SkData> data = picture->serialize(pixel_serializer_);
+  DCHECK_GE(data->size(), 0u);

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

Should this be DCHECK_GT? Is it possible for a picture to serialize to zero
bytes?

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

Well, an empty picture could be zero bytes. I don't know the assumption of the
caller regarding that.

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

Oh my question was just a question, to check that DCHECK_GE really is what we
want here. :)

 
   // Store the picture data until it is sent to the client.
   pictures_.insert(
       std::make_pair(picture->uniqueID(),
-                     cc::PictureData(picture->uniqueID(),
-                                     sk_sp<SkData>(stream.copyToData()))));
+                     cc::PictureData(picture->uniqueID(), data)));
 }
 
 }  // namespace engine
 }  // namespace blimp