Nukes the windowmanager interface

mojo/tools/data/apptests

 # This file contains a list of Mojo gtest unit tests.
 #
 # This must be valid Python. It may use the |config| global that will be a
 # mopy.config.Config object, and must set a |tests| global that will contain the
 # list of tests to run.
 #
 # The entries in |tests| are dictionaries of the following form:
 #   {
 #     # Required URL for apptest.
 #     "test": "mojo:test_app_url",
@@ skipping 30 matching lines @@
   #},
   {
     "test": "mojo:view_manager_apptests",
     "type": "gtest_isolated",
     "shell-args": [
       "--use-headless-config",
       "--url-mappings=mojo:window_manager=mojo:test_window_manager"
     ]
   },
   {
-    "test": "mojo:window_manager_apptests",
-    "shell-args": ["--use-headless-config"]
-  },
-  {
     "test": "mojo:resource_provider_apptests",
   },
 ]