Here, i have attached the PDF, that PDF document contains "Nudi" as an embedded font. When i searching the particular word (that in Nudi font), the search result selecting the word that context next to the exact word.

Link to PDF file (or attach file here):
[sample_pdf.zip](https://github.com/mozilla/pdf.js/files/229582/sample_pdf.zip)

Configuration:
- Web browser and its version: Mozilla 45.0.2
- Operating system and its version: Windows 7
- PDF.js version: 1.4.20-disc

What is the expected behavior? (add screenshot)
![find_01](https://cloud.githubusercontent.com/assets/17423938/14704922/c2e67f2c-07d4-11e6-9320-9aed2578d377.png)

const previous = this._state.findPrevious;
    const currentPageIndex = this._linkService.page - 1;
    const numPages = this._linkService.pagesCount;
    this._highlightMatches = true;
    if (this._dirtyMatch) {
      
      this._dirtyMatch = false;
      this._selected.pageIdx = this._selected.matchIdx = -1;
      this._offset.pageIdx = currentPageIndex;
      this._offset.matchIdx = null;
      this._offset.wrapped = false;
      this._resumePageIdx = null;
      this._pageMatches.length = 0;
      this._pageMatchesLength.length = 0;
      this._matchesCountTotal = 0;
      this._updateAllPages(); 
      for (let i = 0; i < numPages; i++) {
        
        if (this._pendingFindMatches[i] === true) {
          continue;
        }
        this._pendingFindMatches[i] = true;
        this._extractTextPromises[i].then(pageIdx => {
          delete this._pendingFindMatches[pageIdx];
          this._calculateMatch(pageIdx);
        });
      }