SkDocument:  Factories now located in SkPDFDocument.h and SkXPSDocument.h

Change-Id: I48e73b27e52511292c2c0bd51ef0168766f53a80
Reviewed-on: https://skia-review.googlesource.com/152780
Commit-Queue: Hal Canary <halcanary@google.com>
Reviewed-by: Mike Reed <reed@google.com>
37 files changed