Port uses of SkLazyPtr to SkOncePtr.

This gives SkOncePtr a non-trivial destructor that uses std::default_delete
by default.  This is overrideable, as seen in SkColorTable.

SK_DECLARE_STATIC_ONCE_PTR still just leaves its pointers hanging at EOP.

BUG=skia:

No public API changes.
TBR=reed@google.com

Committed: https://skia.googlesource.com/skia/+/a1254acdb344174e761f5061c820559dab64a74c

Review URL: https://codereview.chromium.org/1322933005
24 files changed