Change mojo URLs from mojo://mojo_foo to mojo://foo.

mojo/examples/media_viewer/media_viewer.cc

 // 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 <map>
 #include <string>
 
 #include "base/macros.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/strings/utf_string_conversions.h"
@@ skipping 185 matching lines @@
       public ViewObserver {
  public:
   MediaViewer()
       : shell_(nullptr),
         app_(NULL),
         view_manager_(NULL),
         root_view_(NULL),
         control_view_(NULL),
         content_view_(NULL),
         control_panel_(this) {
-    handler_map_["image/png"] = "mojo:mojo_png_viewer";
+    handler_map_["image/png"] = "mojo:png_viewer";
   }
 
   virtual ~MediaViewer() {
     if (root_view_)
       root_view_->RemoveObserver(this);
   }
 
  private:
   typedef std::map<std::string, std::string> HandlerMap;
 
@@ skipping 102 matching lines @@
   DISALLOW_COPY_AND_ASSIGN(MediaViewer);
 };
 
 }  // namespace examples
 }  // namespace mojo
 
 MojoResult MojoMain(MojoHandle shell_handle) {
   mojo::ApplicationRunnerChromium runner(new mojo::examples::MediaViewer);
   return runner.Run(shell_handle);
 }