Latin extended fonts are missing for loading locally

Problem/Motivation

For performance reason we can enable to load Google fonts locally. Because of that, these google fonts files in woff2 format are already part of the codebase. If site use non basic latin characters, e.g. german, hungarian, slovak, etc these characters are broken.

Steps to reproduce

Use e.g the "Default - Open Sans - sans-serif" google fonts. Enable "Load Google fonts (site fonts and heading fonts only) locally". Add some text with characters, e.g. "German: ä, ö, Hunagrian: ő, ű; Slovak: č, ž."

Proposed resolution

We need latin-ext woff2 fonts too as local files and define in font specific css too, e.g. for Open Sans:

@font-face {
  font-family: 'Open Sans';
  font-style: normal;
  font-weight: 400;
  src: local(''), url('fonts-files/open-sans/open-sans-v27-latin-ext.woff2') format('woff2');
  unicode-range: U+0100-024F, U+0259, U+1E00-1EFF, U+2020, U+20A0-20AB, U+20AD-20CF, U+2113, U+2C60-2C7F, U+A720-A7FF;
}