Move Sky's DataPipeDrainer to mojo/common

mojo/common/BUILD.gn

 # 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.
 
 import("//mojo/public/tools/bindings/mojom.gni")
 
 # GYP version: mojo/mojo_base.gyp:mojo_common_lib
 component("common") {
   output_name = "mojo_common_lib"
 
   sources = [
     "common_type_converters.cc",
     "common_type_converters.h",
     "data_pipe_utils.cc",
     "data_pipe_utils.h",
+    "data_pipe_drainer.h",
+    "data_pipe_drainer.cc",
     "handle_watcher.cc",
     "handle_watcher.h",
     "message_pump_mojo.cc",
     "message_pump_mojo.h",
     "message_pump_mojo_handler.h",
     "time_helper.cc",
     "time_helper.h",
     "weak_binding_set.h",
   ]
 
@@ skipping 40 matching lines @@
     "tracing_impl.h",
   ]
 
   deps = [
     "//base",
     "//mojo/public/cpp/application",
     "//mojo/public/cpp/bindings",
     "//services/tracing:bindings",
   ]
 }