test: Move util/test to its own top-level directory, test

test/multiprocess_exec_test_child.cc

 // Copyright 2014 The Crashpad Authors. All rights reserved.
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
 // You may obtain a copy of the License at
 //
 //     http://www.apache.org/licenses/LICENSE-2.0
 //
 // Unless required by applicable law or agreed to in writing, software
 // distributed under the License is distributed on an "AS IS" BASIS,
@@ skipping 64 matching lines @@
   DWORD bytes_written;
   if (!WriteFile(
           GetStdHandle(STD_OUTPUT_HANDLE), &c, 1, &bytes_written, nullptr) ||
       bytes_written != 1) {
     abort();
   }
 #endif  // OS_POSIX
 
   return 0;
 }