remove T*/void* union in SkTArray

Another memcpy-doesn't-activate-union-fields bug for GCC, I think.

As far as I can tell this union is completely pointless, and this is so
prehistoric git blame doesn't help. (svn blame wouldn't even.)  I don't
really want to know.

Change-Id: I5a67469337752986c6a5979d91cb56417955d019
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/257445
Commit-Queue: Mike Klein <mtklein@google.com>
Reviewed-by: Brian Osman <brianosman@google.com>
1 file changed