Add RendererFactorySelector

media/base/renderer_factory_selector.cc

+// Copyright 2017 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 "media/base/renderer_factory_selector.h"
+
+#include "base/logging.h"
+
+namespace media {
+
+RendererFactorySelector::RendererFactorySelector() {}
+
+RendererFactorySelector::~RendererFactorySelector() {}
+
+void RendererFactorySelector::AddFactory(
+    FactoryType type,
+    std::unique_ptr<RendererFactory> factory) {
+  DCHECK(!factories_[type]);
+
+  factories_[type] = std::move(factory);
+}
+
+void RendererFactorySelector::SetBaseFactoryType(FactoryType type) {
+  DCHECK(factories_[type]);
+  base_factory_type_ = type;
+}
+
+RendererFactory* RendererFactorySelector::GetCurrentFactory() {
+  DCHECK(base_factory_type_);
+  FactoryType next_factory_type = base_factory_type_.value();
+
+  RendererFactory* factory = factories_[next_factory_type].get();
+
+  if (factory == nullptr) {
+    NOTREACHED();
+    return nullptr;
+  }
+
+  DVLOG(1) << __func__ << " Selected factory type: " << next_factory_type;
+
+  return factory;
+}
+
+}  // namespace media