Could you take a look on this file. The first page is mixed with the last page.

[cb7e7bd2362328f37fe97dc8dff151a3.pdf](https://github.com/mozilla/pdf.js/files/1706865/cb7e7bd2362328f37fe97dc8dff151a3.pdf)


Configuration:
- Firefox Nightly 60
- Windows 7
reader.read().then(functn ({ value, dne }) {
          f (dne) {
            return;
          }
          relve(value);
          pu();
        }, reject);
      }
      pu();
    });
    f (data.crenType !== CMapCrenType.NONE) {
      
      th.bultInCMapCache.et(name, data);
    }