mojo: Fix Java binding generator for array<enum> am: e8b2235c46 am: ab05e985a9 am: cfbd04e518 am: 3cf4be303d

Original change: https://android-review.googlesource.com/c/platform/external/libchrome/+/1498099

Change-Id: I5f3de106fcd2b44ed528488b63aa33e88befd2f9