Remove GYP files.

third_party/brotli/bro.gypi

-# Copyright (c) 2016 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.
-
-# Usage:
-# {
-#   'target_name': 'your_target_name',
-#   'type': 'none',
-#   'actions': [
-#     {
-#       'variables': {
-#         'input_file': 'file/to/compress',
-#         'output_file': 'file/to/put/compressed',
-#       },
-#       'includes': ['../third_party/brotli/bro.gypi'],
-#     }
-#   ],
-#   'dependencies': [
-#     'path/to:builds_file_to_compress'
-#   ],
-# },
-
-{
-  'action_name': 'genbro',
-  'variables': {
-    'bro': '<(PRODUCT_DIR)/<(EXECUTABLE_PREFIX)bro<(EXECUTABLE_SUFFIX)',
-  },
-  'inputs': [
-    '<(bro)',
-    '<(input_file)',
-  ],
-  'outputs': [
-    '<(output_file)',
-  ],
-  'action': [
-    '<(bro)',
-    '--force',
-    '--input',
-    '<(input_file)',
-    '--output',
-    '<(output_file)',
-  ],
-  'dependencies': [
-    '<(DEPTH)/third_party/brotli/brotli.gyp:bro#host',
-  ],
-}