Don't use real urls for kiosk_wm just yet.

mojo/devtools/common/mojo_run

Index: mojo/devtools/common/mojo_run
diff --git a/mojo/devtools/common/mojo_run b/mojo/devtools/common/mojo_run
index 06bc6275b22ec17f9e552267fd07a89c32e1b5b6..50992b378b8271e57e52ecf3c4c5041c4440dd46 100755
--- a/mojo/devtools/common/mojo_run
+++ b/mojo/devtools/common/mojo_run
@@ -30,10 +30,9 @@ text/html,mojo:html_viewer,application/javascript,mojo:js_content_handler
 # Port on which the mojo:debugger http server will be available on the host
 # machine.
 _MOJO_DEBUGGER_PORT = 7777
-_DEFAULT_WM = 'https://core.mojoapps.io/kiosk_wm.mojo'
+_DEFAULT_WM = 'mojo:kiosk_wm'
 
-_LEGACY_WM_URL = 'mojo:window_manager'
-_WM_URL = 'https://core.mojoapps.io/window_manager.mojo'
+_WM_URL = 'mojo:window_manager'
 _DEBUGGER_URL = 'https://core.mojoapps.io/debugger.mojo'
 
 
@@ -76,9 +75,6 @@ def main():
     return 1
 
   shell_args = shell_arguments.append_to_argument(shell_args, '--url-mappings=',
-                                                  '%s=%s' % (_LEGACY_WM_URL,
-                                                  script_args.window_manager))
-  shell_args = shell_arguments.append_to_argument(shell_args, '--url-mappings=',
                                                   '%s=%s' % (_WM_URL,
                                                   script_args.window_manager))