Motown: Remove LPCM optimizations, fix prepare, add flush, add ActiveMultistreamSink model/stage

services/media/framework/stages/input.cc

Index: services/media/framework/stages/input.cc
diff --git a/services/media/framework/stages/input.cc b/services/media/framework/stages/input.cc
new file mode 100644
index 0000000000000000000000000000000000000000..b8d466ac1e3b89167154f6e56b28904f7e79f5ee
--- /dev/null
+++ b/services/media/framework/stages/input.cc
@@ -0,0 +1,48 @@
+// 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 "services/media/framework/engine.h"
+#include "services/media/framework/stages/input.h"
+#include "services/media/framework/stages/stage.h"
+
+namespace mojo {
+namespace media {
+
+Input::Input() : prepared_(false) {}
+
+Input::~Input() {}
+
+void Input::Connect(const OutputRef& output) {
+  DCHECK(output.valid());
+  DCHECK(!mate_);
+  mate_ = output;
+}
+
+Output& Input::actual_mate() const {
+  DCHECK(mate_.valid());
+  return mate_.actual();
+}
+
+void Input::SetDemand(Demand demand, Engine* engine) const {
+  DCHECK(engine);
+  DCHECK(connected());
+
+  if (actual_mate().UpdateDemandFromInput(demand)) {
+    engine->PushToDemandBacklog(mate().stage_);
+  }
+}
+
+bool Input::SupplyPacketFromOutput(PacketPtr packet) {
+  DCHECK(packet);
+  DCHECK(!packet_from_upstream_);
+  packet_from_upstream_ = std::move(packet);
+  return true;
+}
+
+void Input::Flush() {
+  packet_from_upstream_.reset(nullptr);
+}
+
+}  // namespace media
+}  // namespace mojo