Ensure visibilitychange and pagehide fire reliably on Android browser

[philipwalton]

Unrelated to this library, @wardpeet (via Twitter) reported that their team researched page lifecycle events and found them to be unreliable on older Android browser.

We should test to ensure this is not the case (or at least doesn't affect this library) and add android browser to the test suite.

[wardpeet]

I'll talk with my collegue what we tried again in the past and try to reproduce if we can remember