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

services/media/framework/stages/stage_output.cc

Index: services/media/framework/stages/stage_output.cc
diff --git a/services/media/framework/stages/stage_output.cc b/services/media/framework/stages/stage_output.cc
deleted file mode 100644
index 34d921f66fb9fbd9454bf11c5182e33c1846656c..0000000000000000000000000000000000000000
--- a/services/media/framework/stages/stage_output.cc
+++ /dev/null
@@ -1,122 +0,0 @@
-// 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/stage.h"
-#include "services/media/framework/stages/stage_output.h"
-
-namespace mojo {
-namespace media {
-
-StageOutput::StageOutput() :
-    downstream_stage_(nullptr),
-    input_index_(0),
-    demand_(Demand::kNegative),
-    copy_allocator_(nullptr) {}
-
-StageOutput::~StageOutput() {}
-
-void StageOutput::connect(Stage* downstream_stage, uint32_t input_index) {
-  DCHECK(downstream_stage);
-  DCHECK(input_index < downstream_stage->input_count());
-  DCHECK(downstream_stage_ == nullptr);
-  downstream_stage_ = downstream_stage;
-  input_index_ = input_index;
-}
-
-StageInput& StageOutput::mate() const {
-  DCHECK(downstream_stage_);
-  DCHECK(input_index_ < downstream_stage_->input_count());
-  return downstream_stage_->input(input_index_);
-}
-
-Allocator* StageOutput::Prepare(bool can_accept_allocator) {
-  DCHECK(connected());
-  StageInput& mate = this->mate();
-  copy_allocator_ = nullptr;
-
-  if (can_accept_allocator) {
-    // We can use an allocator. Use our mate's allocator, if it has one.
-    return mate.allocator();
-  } else if (mate.must_allocate()) {
-    // We can't use an allocator, but our mate needs us to. We'll need to copy
-    // every packet.
-    copy_allocator_ = mate.allocator();
-    DCHECK(copy_allocator_);
-    return nullptr;
-  } else {
-    // We can't use an allocator, and our mate doesn't need us to.
-    return nullptr;
-  }
-}
-
-Demand StageOutput::demand() const {
-  DCHECK(connected());
-
-  // Return negative demand if mate() already has a packet.
-  // We check demand_ here to possibly avoid the second check.
-  if (demand_ == Demand::kNegative || mate().packet_from_upstream()) {
-    return Demand::kNegative;
-  }
-
-  return demand_;
-}
-
-void StageOutput::SupplyPacket(PacketPtr packet, Engine* engine) const {
-  DCHECK(packet);
-  DCHECK(engine);
-  DCHECK(connected());
-
-  if (copy_allocator_ != nullptr) {
-    // Need to copy the packet due to an allocation conflict.
-    uint64_t size = packet->size();
-    void *buffer;
-
-    if (size == 0) {
-      buffer = nullptr;
-    } else {
-      buffer = copy_allocator_->AllocatePayloadBuffer(size);
-      if (buffer == nullptr) {
-        // Starved for buffer space.
-        return;
-      }
-      memcpy(buffer, packet->payload(), size);
-    }
-
-    packet = Packet::Create(
-        packet->presentation_time(),
-        packet->duration(),
-        packet->end_of_stream(),
-        size,
-        buffer,
-        copy_allocator_);
-  }
-
-  SupplyPacketInternal(std::move(packet), engine);
-}
-
-bool StageOutput::UpdateDemand(Demand demand) {
-  if (demand_ == demand) {
-    return false;
-  }
-  demand_ = demand;
-  return true;
-}
-
-LpcmStageOutput* StageOutput::get_lpcm() {
-  return nullptr;
-}
-
-void StageOutput::SupplyPacketInternal(PacketPtr packet, Engine* engine)
-    const {
-  DCHECK(packet);
-  DCHECK(engine);
-  DCHECK(connected());
-  if (mate().SupplyPacketFromOutput(std::move(packet))) {
-    engine->PushToSupplyBacklogUnsafe(downstream_stage());
-  }
-}
-
-}  // namespace media
-}  // namespace mojo