Chrome logs are now enabled for E2E tests when the 'ENABLE_CHROME_LOGS'
environment variable is set to anything other than `false`.
This was helpful to me in debugging Chrome crashes on CI, the ones with
the error "unknown error: DevToolsActivePort file doesn't exist". This
was the only way to discover the cause of the error. It's also useful
for discovering console errors from the background process or from the
UI.
It's disabled by default because it makes the test output quite noisy
and difficult to read.
