Remove SkTDArray::getAt

Change-Id: Iccffc8ebba70501c2792868dc3251acc619c1398
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/586284
Reviewed-by: John Stiles <johnstiles@google.com>
Commit-Queue: Herb Derby <herb@google.com>
2 files changed