Add Number.isNaN and Number.isInteger polyfills in compatibility.js, since the Streams polyfill relies on them

[Snuffleupagus]

Without this, the Streams polyfill will fail in Internet Explorer when the code-paths containing these methods are used.

Please note: This is something that I noticed when testing PR #8617 in IE (all versions). While, in the context of that PR, it would be sufficient to polyfill Number.isNaN I did a quick code search in the Streams polyfill and found Number.isInteger being used as well.

Edit: The patch was updated to remove a spurious blank line, however no functional code changes were made.

[Snuffleupagus]

/botio-linux preview

[pdfjsbot]

From: Bot.io (Linux m4)

---

Received

Command cmd_preview from @Snuffleupagus received. Current queue size: 0

Live output at: http://54.67.70.0:8877/4cc52ee0b041bd2/output.txt

[pdfjsbot]

From: Bot.io (Linux m4)

---

Success

Full output at http://54.67.70.0:8877/4cc52ee0b041bd2/output.txt

Total script time: 2.36 mins

Published

• Viewer: http://54.67.70.0:8877/4cc52ee0b041bd2/web/viewer.html
• Extension: http://54.67.70.0:8877/4cc52ee0b041bd2/extensions/firefox/pdf.js.xpi

[yurydelendik]

Looks good. Can we also replace isInt by Number.isInteger and isNaN by Number.isNaN in our src/ code?

[Snuffleupagus]

Looks good. Can we also replace isInt by Number.isInteger and isNaN by Number.isNaN in our src/ code?

That ought to be possible, especially the part about replacing our existing isInt helper function.
However, given that isNaN has slightly different behaviour than Number.isNaN for non-numbers, this part will most likely require very careful analysis of each case to not accidentally alter the logic.

Since this is a blocker for PR #8617, I'm landing this as-is, and we can look into doing the conversion later on. Thank you for the review!