Since we're only using it on Linux now, just require poppler as a system dependency.

third_party/poppler/config/poppler-version.h

Index: third_party/poppler/config/poppler-version.h
diff --git a/third_party/poppler/config/poppler-version.h b/third_party/poppler/config/poppler-version.h
deleted file mode 100644
index cc0822ef1686c509e94577f4dfa11bf8730005ac..0000000000000000000000000000000000000000
--- a/third_party/poppler/config/poppler-version.h
+++ /dev/null
@@ -1,39 +0,0 @@
-/*
- * Copyright (C) 2009, Pino Toscano <pino@kde.org>
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2, or (at your option)
- * any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, MA 02110-1301, USA.
- */
-
-#ifndef POPPLER_VERSION_H
-#define POPPLER_VERSION_H
-
-#include "poppler-global.h"
-
-#define POPPLER_VERSION "0.22.5"
-#define POPPLER_VERSION_MAJOR 0
-#define POPPLER_VERSION_MINOR 22
-#define POPPLER_VERSION_MICRO 5
-
-namespace poppler
-{
-
-POPPLER_CPP_EXPORT std::string version_string();
-POPPLER_CPP_EXPORT unsigned int version_major();
-POPPLER_CPP_EXPORT unsigned int version_minor();
-POPPLER_CPP_EXPORT unsigned int version_micro();
-
-}
-
-#endif