Revert of Move prefix_set and parts of s_b_util into a new component safe_browsing_db.

components/safe_browsing_db/BUILD.gn

Index: components/safe_browsing_db/BUILD.gn
diff --git a/components/safe_browsing_db/BUILD.gn b/components/safe_browsing_db/BUILD.gn
deleted file mode 100644
index 43541752c6767411cfe39782653d00140d8ed131..0000000000000000000000000000000000000000
--- a/components/safe_browsing_db/BUILD.gn
+++ /dev/null
@@ -1,45 +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.
-
-group("safe_browsing_db") {
-  deps = [
-    ":prefix_set",
-    ":safe_browsing_db_util",
-  ]
-}
-
-source_set("prefix_set") {
-  sources = [
-    "prefix_set.cc",
-    "prefix_set.h",
-  ]
-  deps = [
-    "//base",
-  ]
-}
-
-source_set("safe_browsing_db_util") {
-  sources = [
-    "safe_browsing_db_util.cc",
-    "safe_browsing_db_util.h",
-  ]
-  deps = [
-    "//base",
-    "//crypto",
-  ]
-}
-
-source_set("unit_tests") {
-  testonly = true
-  sources = [
-    "prefix_set_unittest.cc",
-    "safe_browsing_db_util_unittest.cc",
-  ]
-  deps = [
-    ":prefix_set",
-    ":safe_browsing_db_util",
-    "//base",
-    "//testing/gtest",
-  ]
-}