Fix gn bootstrap

R=dpranke

Change-Id: I880c2cc2a2702db6ebbbd90120753587971bb2be
Reviewed-on: https://chromium-review.googlesource.com/1067581
Reviewed-by: Dirk Pranke <dpranke@chromium.org>
Commit-Queue: Thomas Anderson <thomasanderson@chromium.org>
Cr-Original-Commit-Position: refs/heads/master@{#560326}
Cr-Mirrored-From: https://chromium.googlesource.com/chromium/src
Cr-Mirrored-Commit: 3685d34110d27fa6264a58bfb8c21e1880d07ad2

tools/gn/bootstrap/bootstrap.py

diff --git a/tools/gn/bootstrap/bootstrap.py b/tools/gn/bootstrap/bootstrap.py
index ebc3237..9a8e88e 100755
--- a/tools/gn/bootstrap/bootstrap.py
+++ b/tools/gn/bootstrap/bootstrap.py
@@ -600,6 +600,7 @@
       'base/task_scheduler/scoped_set_task_priority_for_current_thread.cc',
       'base/task_scheduler/sequence.cc',
       'base/task_scheduler/sequence_sort_key.cc',
+      'base/task_scheduler/service_thread.cc',
       'base/task_scheduler/task.cc',
       'base/task_scheduler/task_scheduler.cc',
       'base/task_scheduler/task_scheduler_impl.cc',