Reduce the size of pdfium_engine.cc by moving a chunk of code into
pdfium_font_linux.cc. Fix a couple of comments and make a small tweak
along the way.
Change-Id: I503ec6fbf6ebb312bcbd23c9f575ad72c95900d0
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1725332
Reviewed-by: Henrique Nakashima <hnakashima@chromium.org>
Commit-Queue: Lei Zhang <thestig@chromium.org>
Cr-Commit-Position: refs/heads/master@{#682463}