Avoid breaking core tests if `browser` is not available
Environment
Our testing environment fails if browser
is not checked.
See https://gitlab.com/eyeo/adblockplus/adblockpluscore/-/merge_requests/436#note_468469631
How to reproduce
- remove
typeof browser != "undefined"
fromsnippets.js
and see it failing ...
Observed behavior
Modern Firefox is exposing a chrome
global reference, together with a browser
one, but the latter is not needed anymore.
Expected behavior
Checking for typeof netscape
in Firefox case should be enough.