test: Upgrade googlemock 1.7.0 to googletest 1.8.0

Note that with the release of 1.8.0, googlemock and
googletest are unified into a single release.

test/gtest-1.8.0/travis.sh

@@ -0,0 +1,15 @@
+#!/usr/bin/env sh
+set -evx
+env | sort
+
+mkdir build || true
+mkdir build/$GTEST_TARGET || true
+cd build/$GTEST_TARGET
+cmake -Dgtest_build_samples=ON \
+      -Dgmock_build_samples=ON \
+      -Dgtest_build_tests=ON \
+      -Dgmock_build_tests=ON \
+      -DCMAKE_CXX_FLAGS=$CXX_FLAGS \
+      ../../$GTEST_TARGET
+make
+CTEST_OUTPUT_ON_FAILURE=1 make test