Auto merge of #85 - poiru:fix-font-path, r=jdm
Auto merge of #85 - poiru:fix-font-path, r=jdm

Make CTFontDescriptor::font_path() return filesystem path, not URL

Prior to this commit, the return string was in the format
`file:///foo/bar.otf`. We now omit the leading `file://` portion. This
also properly retains characters that are not URL safe.

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servo/core-text-rs