Fix other.test_EMCC_BUILD_DIR on Windows ('/' vs '\' path delimiter comparison issue)
Work around node.js output flush bug https://github.com/joyent/node/issues/1669 to fix other.test_warn_undefined on Windows. The end of the output buffer would not get printed during the test, which would cause the test to fail. See also https://github.com/kripken/emscripten/issues/2582