Revert of Make chrome/common pass "gn check"

chrome/third_party/mozilla_security_manager/BUILD.gn

Index: chrome/third_party/mozilla_security_manager/BUILD.gn
diff --git a/chrome/third_party/mozilla_security_manager/BUILD.gn b/chrome/third_party/mozilla_security_manager/BUILD.gn
deleted file mode 100644
index 8c14453340514c88973e7bca6fcd66271b9c8ff0..0000000000000000000000000000000000000000
--- a/chrome/third_party/mozilla_security_manager/BUILD.gn
+++ /dev/null
@@ -1,19 +0,0 @@
-# Copyright 2015 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.
-
-source_set("mozilla_security_manager") {
-  sources = [
-    "nsNSSCertHelper.cpp",
-    "nsNSSCertHelper.h",
-    "nsNSSCertificate.cpp",
-    "nsNSSCertificate.h",
-    "nsUsageArrayHelper.cpp",
-    "nsUsageArrayHelper.h",
-  ]
-
-  deps = [
-    "//crypto:platform",
-    "//third_party/icu",
-  ]
-}