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This is our first attempt, mostly to feel this out.  Performance and
correctness problems are both possible.  Please revert this if a benchmark even
smells funny.

That said, we've been working on this a while, are pretty confident it's good
stuff, and have had Skia's internal testing entirely switched over for a week.
Parts of Chromium that serialize and deserialize SkPictures are already
switched over.  This CL finishes things off by switching the default
recorded-from-scratch SkPicture to use SkRecord too.

BUG=

Review URL: https://codereview.chromium.org/504823003

Cr-Commit-Position: refs/heads/master@{#292157}