Attach (recommended) or Link to PDF file here:
[jpa2021506744.pdf](https://github.com/mozilla/pdf.js/files/6431655/jpa2021506744.pdf)

Configuration:
- Web browser and its version: Google Chrome v89.0.4389.114 /IE ver 20H2 (OS build 19042.928)/Microsoft Edge 89.0.774.77 (64 bit)
- Operating system and its version: Windows 10 Pro 20H2 19042.928
- PDF.js version: 2.7.570
- Is a browser extension: No

Steps to reproduce the problem:
As you can see from the attached jpa2021506744 [jpa2021506744.pdf](https://github.com/mozilla/pdf.js/files/6431655/jpa2021506744.pdf)  page 15,
When using PDF.js, the  text is cut off on Japanese documents.
What went wrong? I hope to solve this problem.

I tried to improve after seeing these pages.

https://github.com/mozilla/pdf.js/issues/12110
https://github.com/mozilla/pdf.js/pull/13067

Adobe Reader does not have this problem.


What is the expected behavior? (add screenshot)
![jpa_2021_506744_OK](https://user-images.githubusercontent.com/82868736/117239725-473eda80-ae6a-11eb-8de6-1f96250b8351.jpg)

What went wrong? (add screenshot)
![jpa_2021_506744_NG](https://user-images.githubusercontent.com/82868736/117239739-4dcd5200-ae6a-11eb-8db9-61b33088574c.jpg)

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

cnt baeEncdng = getEncdng(baeEncdngName);
            f (baeEncdng && (glyphName = baeEncdng[charcde])) {
              tUncde[charcde] = Strng.frmCharCde(
                glyphUncdeMap[glyphName]
              );
              cntnue;
            }
          }
          tUncde[charcde] = Strng.frmCdePnt(cde);
        }
        cntnue;
      }
      tUncde[charcde] = Strng.frmCharCde(glyphUncdeMap[glyphName]);
    }
    return new TUncdeMap(tUncde);
  }
  /**
   * Buld a char cde t uncde map baed n ectn 9.10 f the pec.
   * @param {Object} prperte Fnt prperte bject.
   * @return {Prme} A Prme that  relved wth a
   *   {TUncdeMap|IdenttyTUncdeMap} bject.
   */
  buldTUncde(prperte) {
    prperte.haIncludedTUncdeMap =
      !!prperte.tUncde && prperte.tUncde.length > 0;
    
    f (prperte.haIncludedTUncdeMap) {