linux/cros: Print a warning when StackDumpSignalHandler calls _exit(1)

base/debug/stack_trace_posix.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/debug/stack_trace.h"
 
 #include <errno.h>
 #include <fcntl.h>
 #include <signal.h>
 #include <stddef.h>
@@ skipping 365 matching lines @@
 
   PrintToStderr("[end of stack trace]\n");
 
 #if defined(OS_MACOSX) && !defined(OS_IOS)
   if (::signal(signal, SIG_DFL) == SIG_ERR)
     _exit(1);
 #else
   // Non-Mac OSes should probably reraise the signal as well, but the Linux
   // sandbox tests break on CrOS devices.
   // https://code.google.com/p/chromium/issues/detail?id=551681
+  PrintToStderr("Calling _exit(1). Core file will not be generated.\n");
   _exit(1);
 #endif  // defined(OS_MACOSX) && !defined(OS_IOS)
 }
 
 class PrintBacktraceOutputHandler : public BacktraceOutputHandler {
  public:
   PrintBacktraceOutputHandler() {}
 
   void HandleOutput(const char* output) override {
     // NOTE: This code MUST be async-signal safe (it's used by in-process
@@ skipping 414 matching lines @@
     *ptr = *start;
     *start++ = ch;
   }
   return buf;
 }
 
 }  // namespace internal
 
 }  // namespace debug
 }  // namespace base