Fix a c_str() use-after-free bug in the printing code.

printing/printing_context_win.cc

 // Copyright (c) 2009 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 "printing/printing_context.h"
 
 #include <winspool.h>
 
 #include "base/file_util.h"
 #include "base/i18n/file_util_icu.h"
@@ skipping 244 matching lines @@
   // Set the flag used by the AbortPrintJob dialog procedure.
   abort_printing_ = false;
 
   in_print_job_ = true;
 
   // Register the application's AbortProc function with GDI.
   if (SP_ERROR == SetAbortProc(context_, &AbortProc))
     return OnError();
 
   DOCINFO di = { sizeof(DOCINFO) };
-  di.lpszDocName = UTF16ToWide(document_name).c_str();
+  const std::wstring& document_name_wide = UTF16ToWide(document_name);
+  di.lpszDocName = document_name_wide.c_str();
 
   // Is there a debug dump directory specified? If so, force to print to a file.
   FilePath debug_dump_path = PrintedDocument::debug_dump_path();
   if (!debug_dump_path.empty()) {
     // Create a filename.
     std::wstring filename;
     Time now(Time::Now());
     filename = base::TimeFormatShortDateNumeric(now);
     filename += L"_";
     filename += base::TimeFormatTimeOfDay(now);
@@ skipping 335 matching lines @@
   if (buf_size) {
     buffer->reset(new uint8[buf_size]);
     memset(buffer->get(), 0, buf_size);
     if (!GetPrinter(printer, level, buffer->get(), buf_size, &buf_size)) {
       buffer->reset();
     }
   }
 }
 
 }  // namespace printing