mac: Fix gn bootstrap after https://codereview.chromium.org/2768933002

That change added a reference to base::CurrentProcessInfo::CreationTime()
in code of base/ that's live in the gn executable.

BUG=none

Review-Url: https://codereview.chromium.org/2778453003
Cr-Original-Commit-Position: refs/heads/master@{#459510}
Cr-Mirrored-From: https://chromium.googlesource.com/chromium/src
Cr-Mirrored-Commit: 64b5d69a2f831f402112dad708a0612f2869aee4
diff --git a/tools/gn/bootstrap/bootstrap.py b/tools/gn/bootstrap/bootstrap.py
index 10dd512..9bad2b4 100755
--- a/tools/gn/bootstrap/bootstrap.py
+++ b/tools/gn/bootstrap/bootstrap.py
@@ -648,6 +648,7 @@
         'base/message_loop/message_pump_mac.mm',
         'base/metrics/field_trial.cc',
         'base/process/process_handle_mac.cc',
+        'base/process/process_info_mac.cc',
         'base/process/process_iterator_mac.cc',
         'base/process/process_metrics_mac.cc',
         'base/strings/sys_string_conversions_mac.mm',