Fix ProcessSingletonWinTest using default profile....

base/process_util_posix.cc

-// Copyright (c) 2006-2008 The Chromium Authors. All rights reserved.
+// Copyright (c) 2010 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 <dirent.h>
 #include <errno.h>
 #include <fcntl.h>
 #include <signal.h>
 #include <stdlib.h>
 #include <sys/resource.h>
 #include <sys/time.h>
@@ skipping 140 matching lines @@
   if (result && wait) {
     int tries = 60;
     // The process may not end immediately due to pending I/O
     bool exited = false;
     while (tries-- > 0) {
       pid_t pid = HANDLE_EINTR(waitpid(process_id, NULL, WNOHANG));
       if (pid == process_id) {
         exited = true;
         break;
       }
+      if (pid == -1) {
+        if (errno == ECHILD) {
+          // The wait may fail with ECHILD if another process also waited for
+          // the same pid, causing the process state to get cleaned up.
+          exited = true;
+          break;
+        }
+        DPLOG(ERROR) << "Error waiting for process " << process_id;
+      }
 
       sleep(1);
     }
 
     if (!exited)
       result = kill(process_id, SIGKILL) == 0;
   }
 
   if (!result)
     DPLOG(ERROR) << "Unable to terminate process " << process_id;
@@ skipping 711 matching lines @@
                       const ProcessFilter* filter) {
   bool exited_cleanly =
       WaitForProcessesToExit(executable_name, wait_milliseconds,
                              filter);
   if (!exited_cleanly)
     KillProcesses(executable_name, exit_code, filter);
   return exited_cleanly;
 }
 
 }  // namespace base