Revert of Add the viewer toolbar to the PDF extension

chrome/browser/resources/pdf/polymer_loader.js

Index: chrome/browser/resources/pdf/polymer_loader.js
diff --git a/chrome/browser/resources/pdf/polymer_loader.js b/chrome/browser/resources/pdf/polymer_loader.js
deleted file mode 100644
index d6199ef2dd4df416782b878cdea326436769c656..0000000000000000000000000000000000000000
--- a/chrome/browser/resources/pdf/polymer_loader.js
+++ /dev/null
@@ -1,12 +0,0 @@
-// Copyright 2013 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.
-
-(function() {
-// This is necessary because polymer currently doesn't handle the configuration
-// where native Custom Elements are available but native Shadow DOM is not.
-// TODO(bshe): remove this line when polymer supports the configuration.
-document.registerElement = undefined;
-
-<include src="../../../../third_party/polymer/platform/platform.js"></include>
-})();