I posted this answer through the iOS app without problems. Previously I tried to posted it (exact same text) through the Android app, but I got this message:
Please fix the following:
Your post appears to contain code that is not properly formatted as code. Please indent all code by 4 spaces using the code toolbar button or the CTRL+K keyboard shortcut. For more editing help, click the [?] toolbar icon.
My code was properly indented though.
P.S. I didn't use in-app markdown toolbar. I formatted my answer manually. Only after I saw the problem, I tried to use the button for code-block formatting, but it didn't change anything.