Add gflags dependency

third_party/gflags/gen/win/include/private/config.h

Index: third_party/gflags/gen/win/include/private/config.h
diff --git a/third_party/gflags/gen/win/include/private/config.h b/third_party/gflags/gen/win/include/private/config.h
new file mode 100644
index 0000000000000000000000000000000000000000..dcca757e493b05559a919984526e7fc0cf8c1e1b
--- /dev/null
+++ b/third_party/gflags/gen/win/include/private/config.h
@@ -0,0 +1,139 @@
+/* src/config.h.in.  Generated from configure.ac by autoheader.  */
+
+/* Sometimes we accidentally #include this config.h instead of the one
+   in .. -- this is particularly true for msys/mingw, which uses the
+   unix config.h but also runs code in the windows directory.
+   */
+#ifdef __MINGW32__
+#include "../config.h"
+#define GOOGLE_GFLAGS_WINDOWS_CONFIG_H_
+#endif
+
+#ifndef GOOGLE_GFLAGS_WINDOWS_CONFIG_H_
+#define GOOGLE_GFLAGS_WINDOWS_CONFIG_H_
+
+/* Always the empty-string on non-windows systems. On windows, should be
+   "__declspec(dllexport)". This way, when we compile the dll, we export our
+   functions/classes. It's safe to define this here because config.h is only
+   used internally, to compile the DLL, and every DLL source file #includes
+   "config.h" before anything else. */
+#ifndef GFLAGS_DLL_DECL
+# define GFLAGS_IS_A_DLL  1   /* not set if you're statically linking */
+# define GFLAGS_DLL_DECL  __declspec(dllexport)
+# define GFLAGS_DLL_DECL_FOR_UNITTESTS  __declspec(dllimport)
+#endif
+
+/* Namespace for Google classes */
+#define GOOGLE_NAMESPACE  ::google
+
+/* Define to 1 if you have the <dlfcn.h> header file. */
+#undef HAVE_DLFCN_H
+
+/* Define to 1 if you have the <fnmatch.h> header file. */
+#undef HAVE_FNMATCH_H
+
+/* Define to 1 if you have the <inttypes.h> header file. */
+#undef HAVE_INTTYPES_H
+
+/* Define to 1 if you have the <memory.h> header file. */
+#undef HAVE_MEMORY_H
+
+/* define if the compiler implements namespaces */
+#define HAVE_NAMESPACES  1
+
+/* Define if you have POSIX threads libraries and header files. */
+#undef HAVE_PTHREAD
+
+/* Define to 1 if you have the `putenv' function. */
+#define HAVE_PUTENV  1
+
+/* Define to 1 if you have the `setenv' function. */
+#undef HAVE_SETENV
+
+/* Define to 1 if you have the <stdint.h> header file. */
+#undef HAVE_STDINT_H
+
+/* Define to 1 if you have the <stdlib.h> header file. */
+#define HAVE_STDLIB_H 1
+
+/* Define to 1 if you have the <strings.h> header file. */
+#undef HAVE_STRINGS_H
+
+/* Define to 1 if you have the <string.h> header file. */
+#define HAVE_STRING_H 1
+
+/* Define to 1 if you have the `strtoll' function. */
+#define HAVE_STRTOLL  1
+
+/* Define to 1 if you have the `strtoq' function. */
+#define HAVE_STRTOQ  1
+
+/* Define to 1 if you have the <sys/stat.h> header file. */
+#define HAVE_SYS_STAT_H 1
+
+/* Define to 1 if you have the <sys/types.h> header file. */
+#define HAVE_SYS_TYPES_H 1
+
+/* Define to 1 if you have the <unistd.h> header file. */
+#undef HAVE_UNISTD_H
+
+/* define if your compiler has __attribute__ */
+#undef HAVE___ATTRIBUTE__
+
+/* Define to the sub-directory in which libtool stores uninstalled libraries.
+   */
+#undef LT_OBJDIR
+
+/* Name of package */
+#undef PACKAGE
+
+/* Define to the address where bug reports for this package should be sent. */
+#undef PACKAGE_BUGREPORT
+
+/* Define to the full name of this package. */
+#undef PACKAGE_NAME
+
+/* Define to the full name and version of this package. */
+#undef PACKAGE_STRING
+
+/* Define to the one symbol short name of this package. */
+#undef PACKAGE_TARNAME
+
+/* Define to the home page for this package. */
+#undef PACKAGE_URL
+
+/* Define to the version of this package. */
+#undef PACKAGE_VERSION
+
+/* Define to necessary symbol if this constant uses a non-standard name on
+   your system. */
+#undef PTHREAD_CREATE_JOINABLE
+
+/* Define to 1 if you have the ANSI C header files. */
+#define STDC_HEADERS  1
+
+/* the namespace where STL code like vector<> is defined */
+#define STL_NAMESPACE  std
+
+/* Version number of package */
+#undef VERSION
+
+/* Stops putting the code inside the Google namespace */
+#define _END_GOOGLE_NAMESPACE_  }
+
+/* Puts following code inside the Google namespace */
+#define _START_GOOGLE_NAMESPACE_  namespace google {
+
+// ---------------------------------------------------------------------
+// Extra stuff not found in config.h.in
+
+// This must be defined before the windows.h is included.  It's needed
+// for mutex.h, to give access to the TryLock method.
+#ifndef _WIN32_WINNT
+# define _WIN32_WINNT 0x0400
+#endif
+
+// TODO(csilvers): include windows/port.h in every relevant source file instead?
+#include "windows/port.h"
+
+#endif  /* GOOGLE_GFLAGS_WINDOWS_CONFIG_H_ */