Add support for distilling arbitrary URLs in DOM Distiller Viewer.

components/dom_distiller/core/url_constants.cc

Index: components/dom_distiller/core/url_constants.cc
diff --git a/components/dom_distiller/core/url_constants.cc b/components/dom_distiller/core/url_constants.cc
new file mode 100644
index 0000000000000000000000000000000000000000..f890807cfb600a88e7bad5b6b78b5663c99be6c1
--- /dev/null
+++ b/components/dom_distiller/core/url_constants.cc
@@ -0,0 +1,13 @@
+// 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.
+
+#include "components/dom_distiller/core/url_constants.h"
+
+namespace dom_distiller {
+
+const char kEntryIdKey[] = "entry_id";
+const char kUrlKey[] = "url";
+const char kCssPath[] = "readability.css";
+
+}  // namespace dom_distiller