Attach (recommended) or Link to PDF file here:
[双引号不正常.pdf](https://github.com/mozilla/pdf.js/files/3533108/default.pdf)


Configuration:
- Web browser and its version:  IE11 , chrome 
- Operating system and its version:  win7
- PDF.js version:  master
- Is a browser extension: nothing 
teps to reproduce the problem:
1. viewer.html web  online preview


What is the expected behavior? (add screenshot)
Displayed in normal characters.

What went wrong? (add screenshot)
![20190823143813](https://user-images.githubusercontent.com/6269307/63571860-062e6600-c5b4-11e9-9fff-75d65cf6bade.png)

Not only the two characters I took screenshots, but also a lot of garbled Chinese punctuation. For example, the Chinese 《》 symbol. But these garbled characters only appear in some specific very old pdf files.

Link to a viewer (if hosted on a site other than mozilla.github.io/pdf.js or as Firefox/Chrome extension):nothing 

} from "./standard_fonts.js";
import {
  getUnicodeForGlyph,
  getUnicodeRangeFor,
  mapSpecialUnicodeValues,
} from "./unicode.js";
import { IdentityToUnicodeMap, ToUnicodeMap } from "./to_unicode_map.js";
import { CFFFont } from "./cff_font.js";
import { FontRendererFactory } from "./font_renderer.js";
import { GlyfTable } from "./glyf.js";
import { IdentityCMap } from "./cmap.js";
import { OpenTypeFileBuilder } from "./opentype_file_builder.js";
import { readUint32 } from "./core_utils.js";
import { Stream } from "./stream.js";
import { Type1Font } from "./type1_font.js";
const PRIVATE_USE_AREAS = [
  [0xe000, 0xf8ff], 
  [0x100000, 0x10fffd], 
];
const PDF_GLYPH_SPACE_UNITS = 1000;
const EXPORT_DATA_PROPERTIES = [
  "ascent",
  "bbox",
  "black",
  "bold",
  "charProcOperatorList",
  "composite",
  "cssFontInfo",
  "data",
  "defaultVMetrics",