Good question! The short answer is no.
JavaScript "load time" is dependent on complexity, latency to fetch files (CDNs, etc.), and other browser-dependent factors.
A tool like Google Analytics receives data about the page (through tracking pixels), but isn't the same as a bonafide web browser.
A tool like Pingdom or Pingometer which monitors a site either does a HEAD or GET request to the page.
In the case of a HEAD
request, no code is downloaded or executed -- only headers.
In the case of a GET
request, code is actually downloaded (and a factor for load time) but not executed.