Added back GTEST_USE_OWN_TR1_TUPLE for Mesos.

Review: https://reviews.apache.org/r/18867

Author: Dominic Hamon

configure.ac

@@ -624,6 +624,11 @@ if test "x$with_cxx11" = "xyes"; then
     ;;
   esac
 
+  # Force gtest to use it's own tuple implementation since 'tr1/tuple'
+  # might not exist (for example, if building with clang).
+  # TODO(dhamon): Upgrade gmock to 1.7 and pass GTEST_LANG_CXX11.
+  CXXFLAGS="-DGTEST_USE_OWN_TR1_TUPLE=1 $CXXFLAGS"
+
   # Also pass the flags to 3rdparty libraries.
   CONFIGURE_ARGS="$CONFIGURE_ARGS CXXFLAGS='$CXXFLAGS'"
 fi