Enable basic drawing with SkRecord-based pictures.

Enable basic drawing with SkRecord-based pictures.

I've tagged all the functions in SkPicture.cpp is // fRecord TODO or // fRecord
OK, depending on whether or not they're totally broken when used from an
SkRecord-based picture.  Obviously next steps are to eliminate all the TODOs,
then clean up the notes.

I converted SkPicture over to smart pointers too.  It's particularly helpful
that the smart pointers initialize to NULL by default.

For now I've got all the SkRecord-based code jammed in at the bottom of the file.  I figure it'll help me keep things straight for a bit, then we can rearrange later.

BUG=skia:
R=robertphillips@google.com

Review URL: https://codereview.chromium.org/333823007