Move Sky's DataPipeDrainer to mojo/common

sky/engine/platform/fetcher/DataPipeDrainer.cpp

-// Copyright 2014 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 "sky/engine/config.h"
-#include "sky/engine/platform/fetcher/DataPipeDrainer.h"
-
-#include "base/bind.h"
-
-namespace blink {
-
-DataPipeDrainer::DataPipeDrainer(Client* client,
-                                 mojo::ScopedDataPipeConsumerHandle source)
-    : client_(client),
-      source_(source.Pass()),
-      weak_factory_(this) {
-  DCHECK(client_);
-  ReadData();
-}
-
-DataPipeDrainer::~DataPipeDrainer() {
-}
-
-void DataPipeDrainer::ReadData() {
-  const void* buffer = nullptr;
-  uint32_t num_bytes = 0;
-  MojoResult rv = BeginReadDataRaw(source_.get(),
-      &buffer, &num_bytes, MOJO_READ_DATA_FLAG_NONE);
-  if (rv == MOJO_RESULT_OK) {
-    client_->OnDataAvailable(buffer, num_bytes);
-    EndReadDataRaw(source_.get(), num_bytes);
-    WaitForData();
-  } else if (rv == MOJO_RESULT_SHOULD_WAIT) {
-    WaitForData();
-  } else if (rv == MOJO_RESULT_FAILED_PRECONDITION) {
-    client_->OnDataComplete();
-  } else {
-    DCHECK(false);
-  }
-}
-
-void DataPipeDrainer::WaitForData() {
-  handle_watcher_.Start(source_.get(),
-      MOJO_HANDLE_SIGNAL_READABLE, MOJO_DEADLINE_INDEFINITE,
-      base::Bind(&DataPipeDrainer::WaitComplete, weak_factory_.GetWeakPtr()));
-}
-
-void DataPipeDrainer::WaitComplete(MojoResult result) {
-  ReadData();
-}
-
-}  // namespace blink