Use SkDocument_PDF_None if pdf support is not enabled.
Use SkDocument_PDF_None if pdf support is not enabled.

https://codereview.chromium.org/1833193002 added the //printing
dependency to //content/test:content_unittests, but when doing a Debug
build, linking content_unittests fails because it tries to reference the
SkDocument::CreatePDF function, which doesn't exists on platforms that
don't enable printing.

BUG= internal b/27859637
TEST= build content_unittests

Review URL: https://codereview.chromium.org/1842473002

Cr-Commit-Position: 972c6d2dc6dd5efdad1377c0d224e03eb8f276f7@{#383789}

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