Delete blimp/helium and remove references to it from dependent targets

blimp/helium/transport.h

-// 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.
-
-#ifndef BLIMP_HELIUM_TRANSPORT_H_
-#define BLIMP_HELIUM_TRANSPORT_H_
-
-#include <memory>
-
-#include "base/callback.h"
-#include "base/cancelable_callback.h"
-#include "blimp/helium/result.h"
-
-namespace blimp {
-namespace helium {
-
-// Pure virtual interface for a helium::Stream factory. Subclasses can use this
-// interface to encapsulate transport-specific stream connection semantics.
-class Transport {
- public:
-  // Callback invoked with the stream and result code of a Connect or Accept
-  // attempt.
-  // The helium::Stream is assumed to be authenticated and ready to use.
-  // If the connection attempt failed, the value of |stream| will be null and
-  // |result| will be set to the relevant error code.
-  using StreamCreatedCallback =
-      base::CancelableCallback<void(std::unique_ptr<Stream> stream,
-                                    Result result)>;
-
-  // Callback to be invoked when the underlying transport transitions
-  // between an offline/unusable state and an online/usable state.
-  using AvailabilityChangedCallback = base::Callback<void(bool)>;
-
-  virtual void SetAvailabilityChangedCallback(
-      const AvailabilityChangedCallback& callback);
-
-  // Asynchronously attempts to connect a new helium::Stream.
-  // Multiple overlapping connection attempts are permitted.
-  // The caller can cancel |cb| if it no longer needs the stream.
-  virtual void Connect(const StreamCreatedCallback& cb) = 0;
-
-  // Accepts an incoming connection from the peer.
-  virtual void Accept(const StreamCreatedCallback& cb) = 0;
-
-  // Returns true if the underlying transport has the necessary resources
-  // and connectivity for Connect and Accept operations.
-  virtual bool IsAvailable() = 0;
-};
-
-}  // namespace helium
-}  // namespace blimp
-
-#endif  // BLIMP_HELIUM_TRANSPORT_H_