Attach (recommended) or Link to PDF file here:
https://www.nta.go.jp/taxes/tetsuzuki/shinsei/annai/joyaku/annai/pdf2/250.pdf

Configuration:
- Web browser and its version: Firefox 81.0a1
- Operating system and its version: Debian 5.6.7-1
- PDF.js version: latest in Firefox nightly
- Is a browser extension: No

Steps to reproduce the problem:
1. Open the pdf and paste the following text "本 店 又 は 主 た る 事 務 所 の 所 在 地" in "Full name" and in "Domicile and residence" textfields
2. Print or Save the pdf 

What is the expected behavior? (add screenshot)
![image](https://user-images.githubusercontent.com/5641725/91207547-30f05480-e709-11ea-9abd-2af5d970dc46.png)

What went wrong? (add screenshot)
![image](https://user-images.githubusercontent.com/5641725/91207663-69902e00-e709-11ea-8a1d-1ddd30cf0621.png)

Link to a viewer (if hosted on a site other than mozilla.github.io/pdf.js or as Firefox/Chrome extension):

var c = Object.create(null);
        while (i < chars.length) {
          this.cMap.readCharCode(chars, i, c);
          charcode = c.charcode;
          var length = c.length;
          i += length;
          
          var isSpace = length === 1 && chars.charCodeAt(i - 1) === 0x20;
          glyph = this._charToGlyph(charcode, isSpace);
          glyphs.push(glyph);
        }
      } else {
        for (i = 0, ii = chars.length; i < ii; ++i) {
          charcode = chars.charCodeAt(i);
          glyph = this._charToGlyph(charcode, charcode === 0x20);
          glyphs.push(glyph);
        }
      }
      
      return (charsCache[charsCacheKey] = glyphs);
    },
    get glyphCacheValues() {
      return Object.values(this.glyphCache);
    },
  };
  return Font;
})();
var ErrorFont = (function ErrorFontClosure() {
  
  function ErrorFont(error) {