Fix extra Japanese font-family settings

[peaceroad]

Additional specification and adjustment of Japanese font environment in Windows environment.

• MS Gothic/MS Mincho is specified first, so it is displayed with top priority. However, I don't think it's very good because the jaggies are noticeable on the display.
• Therefore, I would like to prioritize the BIZ UD fonts added in recent years, and replace them in the order of Yu fonts and then MS fonts.
  • With the standard font settings, the BIZ font also clogs up the margins of punctuation marks, but I think it's better than the Yu/MS font.
• For macOS, I think there will be no problem for the time being by having the Hiragino font specified first.
• In current browsers, it is no longer necessary to specify both English and Japanese when specifying the Japanese font-family. Therefore, I chose to use only English.
  • However, Yu Fonts has different English names ("Yu Gothic", "YuGothic") in Windows and macOS environments... Therefore, it is necessary to specify both.

[JayPanoz]

Hi,

Maintainer of ReadiumCSS here.

I guess this change would be better suited in the source of ReadiumCSS itself, as it would consequently benefit all apps using it. In addition, there is a risk losing it while updating the distribution/built stylesheets navigator-js is using as we’re in the process of updating ReadiumCSS right now, with multiple changes and bug fixes planned. We’ve already started implementing features initially implemented into Thorium for instance.

In branch develop:

• the patch is a module on its own;
• the font-stacks are located in module “base”.

Please let me know if that sounds good to you, and how I can help make the process smoother.

[peaceroad]

@JayPanoz Thank you for following up. I'm going to close this pull request and submit a pull request to Readium-CSS.
If possible, please tell me about the following:

• Did you add ReadiumCSS-ebpaj_fonts_patch.css at the request of ebpaj? I couldn't really understand it by looking at the Readium-CSS commit log. If I were asked to do so, I thought it would be better not to remove the font specification for Japanese names, so I wanted to ask.
• In ReadiumCSS-base.css, I didn't really understand the difference between -RS__baseFontFamily: and the four specifications that follow. Where is the font specified with -RS__baseFontFamily: used? (The four specifications that follow specify the font of the book, right?)

[peaceroad]

For the time being, I submitted a pull request to Readium-CSS. Thank you.
readium/css#146

[danielweck]

Resolution: readium/css#146

[danielweck]

Backport of ReadiumCSS here: 17b86f2