As I understand it, the goal is to handle the situation where clicking an element might:
1. Synchronously load the page
2. Asynchronously load the page
3. Not load the page

Case 1 and 2 are handled by the callback infrastructure setup in this function. Case 3 would otherwise be dealt with as a page load timeout, which is pretty yucky - so we add a shorter timeout to detect whether a page load has started at all. However, this approach is a bit nondeterministic, and runs the risk of incorrectly categorising case 1 or 2 as case 3, if they take too long to start the page load.

My change takes advantage of the fact that synchronous page load (case 1) has completed by the time we finish executing the target function. Therefore, by moving the start point for the pageLoadNotTriggered timeout we only run the risk of incorrectly categorising case 2, thus reducing the likelihood of incorrect behaviour.