Revert of Move fetching logic out of ApplicationManager, eliminate url mappings.

mojo/fetcher/url_resolver.h

-// 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.
-
-#ifndef MOJO_FETCHER_URL_RESOLVER_H_
-#define MOJO_FETCHER_URL_RESOLVER_H_
-
-#include <map>
-#include <set>
-
-#include "base/basictypes.h"
-#include "base/command_line.h"
-#include "base/files/file_path.h"
-#include "url/gurl.h"
-
-namespace mojo {
-namespace fetcher {
-
-// Supports resolving "mojo:" URLs to a file location, with ".mojo" appended.
-class URLResolver {
- public:
-  explicit URLResolver(const GURL& mojo_base_url);
-  ~URLResolver();
-
-  // Resolve the given "mojo:" URL to the URL that should be used to fetch the
-  // code for the corresponding Mojo App.
-  GURL ResolveMojoURL(const GURL& mojo_url) const;
-
- private:
-  GURL mojo_base_url_;
-
-  DISALLOW_COPY_AND_ASSIGN(URLResolver);
-};
-
-}  // namespace fetcher
-}  // namespace mojo
-
-#endif  // MOJO_FETCHER_URL_RESOLVER_H_