Add an initial implementation of the downloads MD settings page.

chrome/browser/resources/settings/downloads_page/downloads_page.css

+/* 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. */
+
+core-label {
+  margin: 10px;
+}
+
+cr-checkbox {
+  margin-right: 10px;

[Jeremy Klein, 2015/03/06 19:40:14]

RTL. Hah, you told me on mine, now I get to tell you on yours :-).

[Oren Blasberg, 2015/03/06 19:53:16]

Done.

+}
+
+cr-input {
+  width: 300px;
+}
+
+cr-input /deep/ #input {
+  /* This ensures that the "Download location" label and the text in the input
+   * itself are vertically aligned. */
+  margin: 0.25em 0;
+}
+
+.location-label {
+  margin-right: 10px;
+}