Adding the minidump unit test to Windows. This test comes from Chromium.

src/client/windows/unittests/client_tests.gyp

 # Copyright (c) 2010, Google Inc.
 # All rights reserved.
 #
 # Redistribution and use in source and binary forms, with or without
 # modification, are permitted provided that the following conditions are
 # met:
 #
 #     * Redistributions of source code must retain the above copyright
 # notice, this list of conditions and the following disclaimer.
 #     * Redistributions in binary form must reproduce the above
@@ skipping 19 matching lines @@
 {
   'includes': [
     '../build/common.gypi',
   ],
   'targets': [
     {
       'target_name': 'client_tests',
       'type': 'executable',
       'sources': [
         'exception_handler_test.cc',
+        'minidump_test.cc',
       ],
       'dependencies': [
         'gtest.gyp:gtest',
         '../breakpad_client.gyp:common',
         '../crash_generation/crash_generation.gyp:crash_generation_client',
         '../handler/exception_handler.gyp:exception_handler',
       ]
     },
   ],
 }