In Emacs 27, doc-view doesn’t to image rescaling if imagemagick is not present. However, since we have native image rescaling now, we want to rescale regardless of imagemagick. I also added convenient centering commands to doc-view.el. Note that the patch is made on Emacs master branch.

Yuan



In GNU Emacs 27.0.91 (build 1, x86_64-apple-darwin19.5.0, NS appkit-1894.50 Version 10.15.5 (Build 19F101))
of 2020-07-07 built on missSilver
Windowing system distributor 'Apple', version 10.3.1894
System Description:  Mac OS X 10.15.5

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