Work around broken std::unique_ptr<const T[]> constructor from std::unique_ptr<T>&& in older libstdc++.

Change-Id: Ie4190800369515168203ff98b3e3fe0e2d790f1a
Reviewed-on: https://skia-review.googlesource.com/8072
Reviewed-by: Robert Phillips <robertphillips@google.com>
2 files changed