fix(apm): check if performance.getEntries() exists

[suke]

performance.getEntries() is not supported by some browsers, so we need to check that it is exists before use it.
see: https://caniuse.com/#feat=mdn-api_performance_getentries

Before submitting a pull request, please take a look at our
Contributing guidelines and verify:

• If you've added code that should be tested, please add tests.
• Ensure your code lints and the test suite passes (yarn lint) & (yarn test).

[kamilogorek]

Thanks!