Revert "EDK: Move //mojo/edk/system/waitable_event* to edk/util."

mojo/edk/system/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_edk.gni")
 import("//testing/test.gni")
 
 if (is_android) {
   import("//build/config/android/config.gni")
   import("//build/config/android/rules.gni")
@@ skipping 86 matching lines @@
     "shared_buffer_dispatcher.cc",
     "shared_buffer_dispatcher.h",
     "simple_dispatcher.cc",
     "simple_dispatcher.h",
     "slave_connection_manager.cc",
     "slave_connection_manager.h",
     "transport_data.cc",
     "transport_data.h",
     "unique_identifier.cc",
     "unique_identifier.h",
+    "waitable_event.cc",
+    "waitable_event.h",
     "waiter.cc",
     "waiter.h",
   ]
 
   all_dependent_configs = [ ":system_config" ]
 
   public_deps = [
     "../embedder",
     "../embedder:delegates",
     "../embedder:platform",
@@ skipping 50 matching lines @@
     "options_validation_unittest.cc",
     "platform_handle_dispatcher_unittest.cc",
     "raw_channel_unittest.cc",
     "remote_data_pipe_impl_unittest.cc",
     "remote_message_pipe_unittest.cc",
     "shared_buffer_dispatcher_unittest.cc",
     "simple_dispatcher_unittest.cc",
     "test_channel_endpoint_client.cc",
     "test_channel_endpoint_client.h",
     "unique_identifier_unittest.cc",
+    "waitable_event_unittest.cc",
     "waiter_test_utils.cc",
     "waiter_test_utils.h",
     "waiter_unittest.cc",
   ]
 
   deps = [
     ":system",
     "//base",
     "//testing/gtest",
   ]
@@ skipping 25 matching lines @@
 
   mojo_edk_deps = [
     # TODO(vtl): Add separate test targets for this.
     "mojo/edk/util:perftests",
 
     "mojo/edk/system/test",
     "mojo/edk/system/test:perf",
     "mojo/edk/test:test_support",
   ]
 }