Add base/check.h or base/check_op.h based on CHECK* macros.

BUG=chromium:1144735
TEST=CQ

Exempt-From-Owner-Approval: Mechanical change involving a lot of owners.
Change-Id: Ia3b037d3d560984dbe94b8137f3782b36196ad7e
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform2/+/2741767
Reviewed-by: Hidehiko Abe <hidehiko@chromium.org>
Commit-Queue: Qijiang Fan <fqj@google.com>
Tested-by: Qijiang Fan <fqj@google.com>
diff --git a/patchpanel/subnet.cc b/patchpanel/subnet.cc
index 8fa6f4b..d1f023b 100644
--- a/patchpanel/subnet.cc
+++ b/patchpanel/subnet.cc
@@ -10,6 +10,7 @@
 #include <utility>
 
 #include <base/bind.h>
+#include <base/check_op.h>
 #include <base/logging.h>
 
 #include "patchpanel/net_util.h"