Revert "Remove 'mojo_' prefix from all mojo applications."

mojo/examples/window_manager/BUILD.gn

 # 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.
 
 import("//build/config/ui.gni")
 import("//mojo/public/tools/bindings/mojom.gni")
 
 assert(use_aura)
 
 shared_library("window_manager") {
-  output_name = "example_window_manager"
+  output_name = "mojo_example_window_manager"
 
   sources = [
     "debug_panel.cc",
     "debug_panel.h",
     "window_manager.cc",
   ]
 
   deps = [
     ":bindings",
     "//base",
@@ skipping 25 matching lines @@
 
 mojom("bindings") {
   sources = [
     "window_manager.mojom",
   ]
   deps = [
     "//mojo/services/public/interfaces/geometry",
   ]
 }