Remove _lowp SkSplicer experiment for now.

SkSplicer is an experiment, and _lowp SkSplicer is an experiment^2.
It's not that it's a bad idea... it just makes working on the main
SkSplicer experiment more complicated.

While not live at head, it'll live on in my heart.

Change-Id: Ib099370be25623e4cf1bbbca211634e3fe92b475
Reviewed-on: https://skia-review.googlesource.com/8112
Reviewed-by: Herb Derby <herb@google.com>
Commit-Queue: Mike Klein <mtklein@chromium.org>
5 files changed