Remove GYP files.

testing/android/junit/junit_test.gyp

-# 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.
-
-{
-  'targets': [
-    {
-      # GN: //testing/android/junit:junit_test_support
-      'target_name': 'junit_test_support',
-      'type': 'none',
-      'dependencies': [
-        '../../../third_party/junit/junit.gyp:junit_jar',
-        '../../../third_party/mockito/mockito.gyp:mockito_jar',
-        '../../../third_party/robolectric/robolectric.gyp:robolectric_jar'
-      ],
-      'variables': {
-        'src_paths': [
-          'java/src',
-        ],
-      },
-      'includes': [
-        '../../../build/host_jar.gypi',
-      ],
-    },
-    {
-      # GN: //testing/android/junit:junit_unittests
-      'target_name': 'junit_unit_tests',
-      'type': 'none',
-      'dependencies': [
-        'junit_test_support',
-      ],
-      'variables': {
-        'main_class': 'org.chromium.testing.local.JunitTestMain',
-        'src_paths': [
-          'javatests/src',
-        ],
-        'wrapper_script_name': 'helper/<(_target_name)',
-      },
-      'includes': [
-        '../../../build/host_jar.gypi',
-      ],
-    },
-  ],
-}