Remove unique_ptr_address_as_pointer_address

std::unique_ptr is not always the same size as a pointer (shame! shame!).
AFAICT I added this terrible hack just to be able to make GrProcessorSet
store unique_ptrs of const GrFP rather than non-const FP, which is in no
way important.

Bug: skia:9908

Change-Id: I6e7eb0c0a7ad3473489e549909fa0b0a9eeec49b
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/270938
Auto-Submit: Brian Salomon <bsalomon@google.com>
Reviewed-by: Greg Daniel <egdaniel@google.com>
Commit-Queue: Greg Daniel <egdaniel@google.com>
Commit-Queue: Brian Salomon <bsalomon@google.com>
7 files changed