Add scroll_offset and scroll_snap to transform_node's traced value

cc/trees/transform_node.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 "base/trace_event/trace_event_argument.h"
 #include "cc/base/math_util.h"
 #include "cc/proto/gfx_conversions.h"
 #include "cc/proto/property_tree.pb.h"
 #include "cc/trees/transform_node.h"
 #include "ui/gfx/geometry/point3_f.h"
@@ skipping 213 matching lines @@
   value->SetInteger("parent_id", parent_id);
   value->SetInteger("owner_id", owner_id);
   MathUtil::AddToTracedValue("pre_local", pre_local, value);
   MathUtil::AddToTracedValue("local", local, value);
   MathUtil::AddToTracedValue("post_local", post_local, value);
   // TODO(sunxd): make frameviewer work without target_id
   value->SetInteger("target_id", 0);
   value->SetInteger("content_target_id", 0);
   value->SetInteger("source_node_id", source_node_id);
   value->SetInteger("sorting_context_id", sorting_context_id);
+  MathUtil::AddToTracedValue("scroll_offset", scroll_offset, value);
+  MathUtil::AddToTracedValue("scroll_snap", scroll_snap, value);
 }
 
 TransformCachedNodeData::TransformCachedNodeData()
     : target_id(-1), content_target_id(-1) {}
 
 TransformCachedNodeData::TransformCachedNodeData(
     const TransformCachedNodeData& other) = default;
 
 TransformCachedNodeData::~TransformCachedNodeData() {}
 
@@ skipping 19 matching lines @@
     const proto::TransformCachedNodeData& proto) {
   from_target = ProtoToTransform(proto.from_target());
   to_target = ProtoToTransform(proto.to_target());
   from_screen = ProtoToTransform(proto.from_screen());
   to_screen = ProtoToTransform(proto.to_screen());
   target_id = proto.target_id();
   content_target_id = proto.content_target_id();
 }
 
 }  // namespace cc