Attach (recommended) or Link to PDF file here:
[298865.pdf](https://github.com/mozilla/pdf.js/files/2753236/298865.pdf)


Configuration:
- Web browser and its version:chrome 71.0.3578.98
- Operating system and its version:mac os 10.12.6
- PDF.js version:I use online demo in github
- Is a browser extension:no

Steps to reproduce the problem:
1. search "中华" or "电力" or so on,the highlight position is not right

What is the expected behavior? (add screenshot)
![image](https://user-images.githubusercontent.com/10000986/51087378-7eff5100-178d-11e9-991a-005d77b82f31.png)

What went wrong? (add screenshot)
![image](https://user-images.githubusercontent.com/10000986/51087374-6ee77180-178d-11e9-9707-281924f95fd0.png)

Link to a viewer (if hosted on a site other than mozilla.github.io/pdf.js or as Firefox/Chrome extension):
https://mozilla.github.io/pdf.js/web/viewer.html
PasswordException,
  PasswordResponses,
  PermissionFlag,
  StreamType,
} from "../../src/shared/util.js";
import {
  buildGetDocumentParams,
  DefaultFileReaderFactory,
  TEST_PDFS_PATH,
} from "./test_utils.js";
import {
  DefaultCanvasFactory,
  getDocument,
  PDFDataRangeTransport,
  PDFDocumentLoadingTask,
  PDFDocumentProxy,
  PDFPageProxy,
  PDFWorker,
  RenderTask,
} from "../../src/display/api.js";
import {
  RenderingCancelledException,
  StatTimer,
} from "../../src/display/display_utils.js";
import { AutoPrintRegExp } from "../../web/ui_utils.js";
import { GlobalImageCache } from "../../src/core/image_utils.js";
import { GlobalWorkerOptions } from "../../src/display/worker_options.js";
import { isNodeJS } from "../../src/shared/is_node.js";
import { Metadata } from "../../src/display/metadata.js";
describe("api", function () {