Add title &titleTime to Chrome results

If title is set when DOMContentLoaded is fired then pass details to wptdriver.

titleTime is inaccurate as we're waiting for DCL to fire rather than detecting the title appearing

Could poll the DOM instead but that seems overkill, may be able to use MutationObservers instead, ideally Chrome would fire chrome.tabs.onUpdated when the title changes (https://code.google.com/p/chromium/issues/detail?id=395155)