include what you use: errno.h in exec_process.cc

tools/gn/exec_process.cc

 // Copyright 2014 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/command_line.h"
 #include "base/files/file_util.h"
 #include "base/logging.h"
 #include "base/process/kill.h"
 #include "base/process/launch.h"
 #include "base/process/process.h"
 
 #if defined(OS_WIN)
 #include <windows.h>
 
 #include "base/win/scoped_handle.h"
 #include "base/win/scoped_process_information.h"
+#else
+#include <errno.h>

[tfarina, 2015/11/07 16:10:56]

Maybe do this in the POSIX case below?

[Mostyn Bramley-Moore, 2015/11/07 19:52:39]

In this file errno is only used inside the else block of an OS_WIN condition, so
I think this is possibly (very) slightly more accurate.  But this is personal
preference, really.  

Maybe we should just include errno.h unconditionally- I believe this is safe.

[tfarina, 2015/11/08 13:59:33]

Then should we move the includes below in this else instead?

[Mostyn Bramley-Moore, 2015/11/09 16:40:07]

I will defer to Brett on this.

[brettw, 2015/11/10 21:48:19]

Personally I'd merge them all into the else.

[Mostyn Bramley-Moore, 2015/11/10 22:24:22]

Done.

 #endif
 
 #if defined(OS_POSIX)
 #include <fcntl.h>
 #include <unistd.h>
 
 #include "base/posix/eintr_wrapper.h"
 #include "base/posix/file_descriptor_shuffle.h"
 #endif
 
@@ skipping 218 matching lines @@
         return process.WaitForExit(exit_code);
       }
   }
 
   return false;
 }
 #endif
 
 }  // namespace internal