Add user_prefs and visitedlink components to GN build.

components/visitedlink/renderer/BUILD.gn

Index: components/visitedlink/renderer/BUILD.gn
diff --git a/components/visitedlink/renderer/BUILD.gn b/components/visitedlink/renderer/BUILD.gn
new file mode 100644
index 0000000000000000000000000000000000000000..33618cccb69ac561d186c0fdf17b3eeadc75789f
--- /dev/null
+++ b/components/visitedlink/renderer/BUILD.gn
@@ -0,0 +1,20 @@
+# Copyright 2014 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.
+
+if (!is_ios) {
+  static_library("renderer") {
+    output_name = "visitedlink_renderer"
+    sources = [
+      "visitedlink_slave.cc",
+      "visitedlink_slave.h",
+    ]
+
+    deps = [
+      "//base",
+      "//content/public/common",
+      "//content/public/renderer",
+      "//third_party/WebKit/public:blink",
+    ]
+  }
+}