[PPAPI] Compositor API implementation

ppapi/shared_impl/compositor_layer_data.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 "ppapi/shared_impl/compositor_layer_data.h"
+
+namespace ppapi {
+
+namespace {
+
+template<typename T>
+void Copy(scoped_ptr<T>* a, const scoped_ptr<T>& b) {
+  if (b) {
+    if (!(*a))
+      a->reset(new T());
+    **a = *b;
+  } else {
+    a->reset();
+  }
+}
+
+}  // namespace
+
+const CompositorLayerData& CompositorLayerData::operator=(
+    const CompositorLayerData& other) {
+  DCHECK(other.is_null() || other.is_valid());
+
+  common = other.common;
+  Copy(&color, other.color);
+  Copy(&texture, other.texture);
+  Copy(&image, other.image);
+
+  return *this;
+}
+
+}  // namespace ppapi