only install chrome when needed on travis
only install chrome when needed on travis

teamcapybara/capybara,teamcapybara/capybara,teamcapybara/capybara,twalpole/capybara,twalpole/capybara,jnicklas/capybara,olivierlacan/capybara,jnicklas/capybara,olivierlacan/capybara,jnicklas/capybara,twalpole/capybara,olivierlacan/capybara