||This test will measure the performance of opening a tab and displaying
the simplest content (a blank page). This test is concerned primarily
with the time it takes to show the content area to the user, rather than
the performance of the tab opening or closing animations (which are
measured in the TART test). This is why this test disables tab animations.
When opening tabs and showing content, there are two cases to consider:
1) The tab has been opened via a command from the parent process. For example,
the user has clicked on a link in a separate application which is opening
in this browser, so the message to open the tab and display the content
comes from the operating system, to the parent.
2) The tab has been opened by clicking on a link in content. It is possible
for certain types of links (_blank links for example) to open new tabs.
||When a page is loaded, we expect a search string to be
appended with the "starting time" (in ms) of when the tab