tidy up SkTHash special methods

Like the destructors, most of these can just go unspoken.

SkTArray only knows its size in Debug builds, so it can't easily grow a
copy constructor.  Instead just keep the explicit copies and moves on
SkTHashTable, and mark the others as explicitly default.  I inverted the
pattern from assign-by-copy to copy-by-assign, but it's all basically
the same.

Change-Id: I0df552ef547ce9c7e232267c072a5f3b09197847
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/324056
Commit-Queue: Mike Klein <mtklein@google.com>
Reviewed-by: John Stiles <johnstiles@google.com>
1 file changed