Allow layers to signal that additional sequences are needed before surface destruction

cc/layers/surface_holder.cc

+// Copyright 2014 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 "cc/layers/surface_holder.h"
+
+#include "cc/layers/surface_layer.h"
+#include "cc/surfaces/surface.h"
+#include "cc/surfaces/surface_manager.h"
+#include "cc/trees/layer_tree_host.h"
+
+namespace cc {
+
+SurfaceHolder::SurfaceHolder(SurfaceId id, SatisfyCallback callback)
+    : id_(id), satisfy_callback_(callback) {
+}
+
+SurfaceHolder::~SurfaceHolder() {
+  DCHECK(sequences_.empty())
+      << ": SurfaceLayer attached to LayerTreeHost after GetSequenceSet called";
+}
+
+void SurfaceHolder::AddSurfaceSequence(SurfaceSequence sequence) {
+  sequences_.insert(sequence);
+}
+
+void SurfaceHolder::GetSequenceSet(std::set<SurfaceSequence>* sequences) {
+  sequences_.swap(*sequences);
+}
+
+}  // namespace cc