Add back one left out compiler test to angle_unittests VariablePacker_test.cpp The other one UnrollFlatten_test.cpp crashes. BUG= TEST=angle_unittests Change-Id: I78e6e81e9b61f2a1599a5a0601b5b76165b180de Reviewed-on: https://chromium-review.googlesource.com/295767 Reviewed-by: Zhenyao Mo <zmo@chromium.org> Tested-by: Zhenyao Mo <zmo@chromium.org>