Print Preview: Check the result from GetPrintPreviewData() and return on failure.

chrome/browser/ui/webui/print_preview_handler.cc

 // Copyright (c) 2011 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 "chrome/browser/ui/webui/print_preview_handler.h"
 
 #include <string>
 
 #include "base/i18n/file_util_icu.h"
 #include "base/json/json_reader.h"
@@ skipping 430 matching lines @@
       preview_tab(),
       platform_util::GetTopLevel(preview_tab()->GetNativeView()),
       NULL);
 }
 
 void PrintPreviewHandler::FileSelected(const FilePath& path,
                                        int index, void* params) {
   PrintPreviewUIHTMLSource::PrintPreviewData data;
   PrintPreviewUI* print_preview_ui = static_cast<PrintPreviewUI*>(web_ui_);
   print_preview_ui->html_source()->GetPrintPreviewData(&data);
-  DCHECK(data.first);
-  DCHECK_GT(data.second, 0U);
+  if (!data.first || !data.second) {
+    NOTREACHED();
+    return;
+  }
 
   printing::PreviewMetafile* metafile = new printing::PreviewMetafile;
   metafile->InitFromData(data.first->memory(), data.second);
 
   // Updating last_saved_path_ to the newly selected folder.
   *last_saved_path_ = path.DirName();
 
   PrintToPdfTask* task = new PrintToPdfTask(metafile, path);
   BrowserThread::PostTask(BrowserThread::FILE, FROM_HERE, task);
 
   ActivateInitiatorTabAndClosePreviewTab();
 }