Add gmock into our dependencies.

third_party/boost/boost/type_traits/detail/false_result.hpp

Index: third_party/boost/boost/type_traits/detail/false_result.hpp
diff --git a/third_party/boost/boost/type_traits/detail/false_result.hpp b/third_party/boost/boost/type_traits/detail/false_result.hpp
new file mode 100644
index 0000000000000000000000000000000000000000..e65e8bc257c3ddbc7fba2a9446938db45e5a2c9d
--- /dev/null
+++ b/third_party/boost/boost/type_traits/detail/false_result.hpp
@@ -0,0 +1,28 @@
+//  Copyright David Abrahams 2002. 
+//  Use, modification and distribution are subject to the Boost Software License,
+//  Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
+//  http://www.boost.org/LICENSE_1_0.txt).
+//
+//  See http://www.boost.org/libs/type_traits for most recent version including documentation.
+
+
+#ifndef BOOST_TT_DETAIL_FALSE_RESULT_HPP_INCLUDED
+#define BOOST_TT_DETAIL_FALSE_RESULT_HPP_INCLUDED
+
+#include <boost/config.hpp>
+
+namespace boost {
+namespace type_traits {
+
+// Utility class which always "returns" false
+struct false_result
+{
+    template <typename T> struct result_
+    {
+        BOOST_STATIC_CONSTANT(bool, value = false);
+    };
+};
+
+}} // namespace boost::type_traits
+
+#endif // BOOST_TT_DETAIL_FALSE_RESULT_HPP_INCLUDED