DOM input events vs. setTimeout/setInterval order

I have a block of JavaScript code running on my page; let's call it func1. It takes several milliseconds to run. While that code is running, the user may click, move the mouse, enter some keyboard input, etc. I have another block of code, func2, that I want to run after all of those queued-up input events have resolved. That is, I want to ensure the order:

1. func1
2. All handlers bound to input events that occurred while func1 was running
3. func2

My question is: Is calling setTimeout func2, 0 at the end of func1 sufficient to guarantee this ordering, across all modern browsers? What if that line came at the beginning of func1—what order should I expect in that case?

Please back up your answers with either references to the relevant specs, or test cases.

Update: It turns out that no, it's not sufficient. What I failed to realize in my original question was that input events aren't even added to the queue until the current code block has been executed. So if I write

// time-consuming loop...
setTimeout func2, 0

then only after that setTimeout is run will any input events (clicks, etc.) that occurred during the time-consuming loop be queued. (To test this, note that if you remove, say, an onclick callback immediately after the time-consuming loop, then clicks that happened during the loop won't trigger that callback.) So func2 is queued first and takes precedence.

Setting a timeout of 1 seemed to work around the issue in Chrome and Safari, but in Firefox, I saw input events resolving after timeouts as high as 80 (!). So a purely time-based approach clearly isn't going to do what I want.

Nor is it sufficient to simply wrap one setT