Support FileDescriptorWatcher in TaskScheduler.

base/BUILD.gn

 # Copyright (c) 2013 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.
 
 # HOW TO WRITE CONDITIONALS IN THIS FILE
 # ======================================
 #
 # In many other places, one would write a conditional that expresses all the
 # cases when a source file is used or unused, and then either add or subtract
 # it from the sources list in that case
@@ skipping 795 matching lines @@
     "task_scheduler/sequence_sort_key.cc",
     "task_scheduler/sequence_sort_key.h",
     "task_scheduler/task.cc",
     "task_scheduler/task.h",
     "task_scheduler/task_scheduler.cc",
     "task_scheduler/task_scheduler.h",
     "task_scheduler/task_scheduler_impl.cc",
     "task_scheduler/task_scheduler_impl.h",
     "task_scheduler/task_tracker.cc",
     "task_scheduler/task_tracker.h",
+    "task_scheduler/task_tracker_posix.cc",
+    "task_scheduler/task_tracker_posix.h",
     "task_scheduler/task_traits.cc",
     "task_scheduler/task_traits.h",
     "template_util.h",
     "third_party/dmg_fp/dmg_fp.h",
     "third_party/dmg_fp/dtoa_wrapper.cc",
     "third_party/dmg_fp/g_fmt.cc",
     "third_party/icu/icu_utf.cc",
     "third_party/icu/icu_utf.h",
     "third_party/nspr/prtime.cc",
     "third_party/nspr/prtime.h",
@@ skipping 343 matching lines @@
         "files/file_util_posix.cc",
         "json/json_file_value_serializer.cc",
         "json/json_file_value_serializer.h",
         "message_loop/message_pump_libevent.cc",
         "message_loop/message_pump_libevent.h",
         "process/kill_posix.cc",
         "process/launch.cc",
         "process/launch.h",
         "process/launch_posix.cc",
         "rand_util_posix.cc",
+        "task_scheduler/task_tracker_posix.cc",
+        "task_scheduler/task_tracker_posix.h",
       ]
     }
   } else {
     # Remove NaCl stuff.
     sources -= [
       "memory/shared_memory_nacl.cc",
       "os_compat_nacl.cc",
       "os_compat_nacl.h",
       "rand_util_nacl.cc",
       "synchronization/read_write_lock_nacl.cc",
@@ skipping 1259 matching lines @@
     testonly = true
     deps = [
       ":base_java",
     ]
     java_files = [
       "test/android/java/src/org/chromium/base/ContentUriTestUtils.java",
       "test/android/java/src/org/chromium/base/TestSystemMessageHandler.java",
     ]
   }
 }