Use std::vector in process launch code.

base/process/launch_mac.cc

 // 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.
 
 #include "base/process/launch.h"
 
 #include <crt_externs.h>
 #include <mach/mach.h>
 #include <spawn.h>
 #include <string.h>
@@ skipping 122 matching lines @@
   if (null_stdin) {
     file_actions.Open(STDIN_FILENO, "/dev/null", O_RDONLY);
   }
   if (inherit_stdout) {
     file_actions.Inherit(STDOUT_FILENO);
   }
   if (inherit_stderr) {
     file_actions.Inherit(STDERR_FILENO);
   }
 
-  std::unique_ptr<char* []> argv_cstr(new char*[argv.size() + 1]);
-  for (size_t i = 0; i < argv.size(); i++) {
-    argv_cstr[i] = const_cast<char*>(argv[i].c_str());
-  }
-  argv_cstr[argv.size()] = nullptr;
+  std::vector<char*> argv_cstr;
+  argv_cstr.reserve(argv.size() + 1);
+  for (const auto& arg : argv)
+    argv_cstr.push_back(const_cast<char*>(arg.c_str()));
+  argv_cstr.push_back(nullptr);
 
   std::unique_ptr<char* []> owned_environ;
   char** new_environ = options.clear_environ ? nullptr : *_NSGetEnviron();
   if (!options.environ.empty()) {
     owned_environ = AlterEnvironment(new_environ, options.environ);
     new_environ = owned_environ.get();
   }
 
   const char* executable_path = !options.real_path.empty()
                                     ? options.real_path.value().c_str()
@@ skipping 15 matching lines @@
     // finish is the sort of thing ThreadRestrictions is trying to prevent.
     base::ThreadRestrictions::AssertIOAllowed();
     pid_t ret = HANDLE_EINTR(waitpid(pid, nullptr, 0));
     DPCHECK(ret > 0);
   }
 
   return Process(pid);
 }
 
 }  // namespace base