tl;dr

Add <meta name="google" content="notranslate" /> to the head of your page to stop Google offering to translate it.

--verbose

I was recently building a page where the user could provide translations for a given piece of text.

Chromes usual “would you like to translate it” dropdown was getting very annoying. After some light googling I came across a fix. Just add <meta name="google" content="notranslate" /> to the head of your page to stop Google offering to translate it.

There are a whole set of Meta tags that Google understands, have a look here.