L2CAP Data pipeline rework

Currently Scheduler is the overall manager for data pipeline subsystem.
Make a separate manager in the next step.

Bug: 144097774
Test: run_cert.sh
Change-Id: Id331494a49435ca64ae253157e30e5e09c8ae500
diff --git a/gd/l2cap/internal/enhanced_retransmission_mode_channel_data_controller.h b/gd/l2cap/internal/enhanced_retransmission_mode_channel_data_controller.h
new file mode 100644
index 0000000..7db179c
--- /dev/null
+++ b/gd/l2cap/internal/enhanced_retransmission_mode_channel_data_controller.h
@@ -0,0 +1,60 @@
+/*
+ * Copyright 2019 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#pragma once
+
+#include <memory>
+#include <unordered_map>
+#include <utility>
+
+#include "common/bidi_queue.h"
+#include "l2cap/cid.h"
+#include "l2cap/internal/channel_impl.h"
+#include "l2cap/internal/data_controller.h"
+#include "l2cap/internal/scheduler.h"
+#include "l2cap/l2cap_packets.h"
+#include "l2cap/mtu.h"
+#include "os/handler.h"
+#include "os/queue.h"
+#include "packet/base_packet_builder.h"
+#include "packet/packet_view.h"
+
+namespace bluetooth {
+namespace l2cap {
+namespace internal {
+
+class ErtmController : public DataController {
+ public:
+  using UpperEnqueue = packet::PacketView<packet::kLittleEndian>;
+  using UpperDequeue = packet::BasePacketBuilder;
+  using UpperQueueDownEnd = common::BidiQueueEnd<UpperEnqueue, UpperDequeue>;
+  ErtmController(Cid cid, Cid remote_cid, UpperQueueDownEnd* channel_queue_end, os::Handler* handler,
+                 Scheduler* scheduler);
+  void OnSdu(std::unique_ptr<packet::BasePacketBuilder> sdu) override;
+  void OnPdu(BasicFrameView pdu) override;
+  std::unique_ptr<BasicFrameBuilder> GetNextPacket() override;
+
+ private:
+  [[maybe_unused]] Cid cid_;
+  [[maybe_unused]] os::EnqueueBuffer<UpperEnqueue> enqueue_buffer_;
+  [[maybe_unused]] os::Handler* handler_;
+  std::queue<std::unique_ptr<BasicFrameBuilder>> pdu_queue_;
+  [[maybe_unused]] Scheduler* scheduler_;
+};
+
+}  // namespace internal
+}  // namespace l2cap
+}  // namespace bluetooth