Fixes import file name from error.h to errno.h

Patch crrev.com/c/2326511 incorrectly imports <error.h> instead of
<errno.h> to access char* program_invocation_short_name.

It should be <errno.h> that is imported.
https://linux.die.net/man/3/program_invocation_short_name

BUG=chromium:1110865
TEST=run `ps aux` on a chromebook

Change-Id: I24f687cab02eaa34efe87d4d209cbb437021d9f7
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2352250Reviewed-by: Scott Violet <sky@chromium.org>
Reviewed-by: Lei Zhang <thestig@chromium.org>
Commit-Queue: Yuta Hijikata <ythjkt@chromium.org>
Cr-Commit-Position: refs/heads/master@{#797512}

services/service_manager/embedder/set_process_title.cc

@@ -2,9 +2,9 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-// Define _GNU_SOURCE to ensure that <error.h> defines
+// Define _GNU_SOURCE to ensure that <errno.h> defines
 // program_invocation_short_name. Keep this at the top of the file since some
-// system headers might include <error.h> and the header could be skipped on
+// system headers might include <errno.h> and the header could be skipped on
 // subsequent includes.
 #if defined(OS_LINUX) && !defined(_GNU_SOURCE)
 #define _GNU_SOURCE
@@ -27,7 +27,7 @@
 #endif  // defined(OS_POSIX) && !defined(OS_MAC) && !defined(OS_SOLARIS)
 
 #if defined(OS_LINUX)
-#include <error.h>  // Get program_invocation_short_name declaration.
+#include <errno.h>  // Get program_invocation_short_name declaration.
 #include <sys/prctl.h>
 
 #include "base/files/file_path.h"