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_.count(type));
+
+  factories_.emplace(type, std::move(factory));
+}
+
+void RendererFactorySelector::SetBaseFactoryType(FactoryType type) {
+  DCHECK(factories_.count(type));
+  base_factory_type_ = type;
+}
+
+RendererFactory* RendererFactorySelector::GetCurrentFactory() {
+  DCHECK_NE(base_factory_type_, FactoryType::UNKNOWN);
+
+  auto it = factories_.find(base_factory_type_);
+
+  if (it == factories_.end()) {
+    NOTREACHED();
+    return nullptr;
+  }
+
+  DVLOG(1) << __func__ << " Selected factory type: " << it->first;
+
+  return it->second.get();
+}
+
+}  // namespace media