buildtools support mingw
Merge branch 'master' into refs/top-bases/t/3rdTools/zlib
Merge commit 'refs/top-bases/t/3rdTools/zlib' into t/3rdTools/zlib
Merge branch 'master' into refs/top-bases/t/3rdTools/libpng
Merge branch 't/3rdTools/zlib' into refs/top-bases/t/3rdTools/libpng
Merge commit 'refs/top-bases/t/3rdTools/libpng' into t/3rdTools/libpng