Introduce //components/user_prefs, use to eliminate c/b/prefs dependency in Autofill.

components/user_prefs.gypi

+# Copyright (c) 2013 The Chromium Authors. All rights reserved.

[tfarina, 2013/02/27 15:17:50]

no (c) ?

+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+{
+  'targets': [
+    {
+      'target_name': 'user_prefs',
+      'type': '<(component)',
+      'dependencies': [
+        '../base/base.gyp:base',
+        '../base/base.gyp:base_prefs',
+        '../base/base.gyp:base_prefs',

[tfarina, 2013/02/27 15:17:50]

duplicated

+        '../ui/ui.gyp:ui',
+      ],
+      'include_dirs': [
+        '..',
+      ],
+      'defines': [
+        'USER_PREFS_IMPLEMENTATION',
+      ],
+      'sources': [
+        'user_prefs/pref_registry_syncable.cc',
+        'user_prefs/pref_registry_syncable.h',
+        'user_prefs/user_prefs.cc',
+        'user_prefs/user_prefs.h',
+        'user_prefs/user_prefs_export.h',
+      ],
+    },
+  ],
+}