Populate download_file_types proto and filter it for each platform

chrome/chrome_resources.gyp

 # Copyright (c) 2012 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.
 {
   'variables': {
     # Apply Chrome-specific grit settings to all of this file.
     # The advantage is that one entry here applies to the entire file.
     # The caveat is these variables cannot be merged with other variable
     # dictionaries in more inner scopes. If the variable should be merged,
     # consider putting them in a gypi file and including it at the right scope
@@ skipping 296 matching lines @@
         'chrome.gyp:safe_browsing_proto',
         '<(DEPTH)/third_party/protobuf/protobuf.gyp:py_proto',
       ],
       'actions': [
         {
           'action_name': 'generate_file_types_protobuf',
           'variables' : {
             'script_file':'browser/resources/safe_browsing/gen_file_type_proto.py',
             'asciipb_file' : 'browser/resources/safe_browsing/download_file_types.asciipb',
             'output_file' : '<(SHARED_INTERMEDIATE_DIR)/chrome/browser/resources/safe_browsing/download_file_types.pb',
+            'conditions': [
+              ['OS=="android"', {
+                'platform': 'android'
+              }, 'chromeos==1', {
+                'platform': 'chromeos'
+              }, 'OS=="linux"', {
+                'platform': 'linux'
+              }, 'OS=="mac"', {
+                'platform': 'mac'
+              }, 'OS=="win"', {
+                'platform': 'win'
+              }, {
+                # This will cause the script to fail
+                'platform': 'unknown_target_arch'
+              }],
+            ],
           },
           'inputs': [
             '<(script_file)',
             '<(asciipb_file)',
           ],
           'outputs': [
             '<(output_file)',
           ],
           'action': [
             'python',
             '<(script_file)',
             '-w',
             '-i', '<(asciipb_file)',
             '-o', '<(output_file)',
+            '-t', '<(platform)',
             '-p', '<(PRODUCT_DIR)/pyproto',
             '-p', '<(PRODUCT_DIR)/pyproto/chrome/common/safe_browsing',
           ],
           'message': 'Generating download_file_types.pb.',
         }
       ],
     },
     {
       # GN version: //chrome/browser/metrics/variations:chrome_ui_string_overrider_factory_gen_sources
       'target_name': 'make_chrome_ui_string_overrider_factory',
@@ skipping 382 matching lines @@
               '<(SHARED_INTERMEDIATE_DIR)/chrome/webui_test_resources.pak',
             ],
             'pak_output': '<(PRODUCT_DIR)/browser_tests.pak',
           },
           'includes': [ '../build/repack_action.gypi' ],
         },
       ],
     },
   ], # targets
 }