standardizing Error.stack or equivalent

[Boris Zbarsky]

On 3/27/14 12:31 PM, Mark Miller wrote:
> Mozillians, why did you add this extra information?

Looks like it was added in 
https://bugzilla.mozilla.org/show_bug.cgi?id=332176

Before that, the stack claimed the url of the caller of eval() but a 
line number which was the sum of the line number of the eval() call 
itself and the line number of the code throwing the exception inside the 
eval string, I believe, or some such insanity.

There's a lot of noise there in the discussion, but I think the key 
recent part is comment 40 in the above bug, which summarizes what I 
think we implemented.  Note that per comment 42 we do something similar 
for new Function() as well, so you can get a stack trace like so:

anonymous at url line 3 > Function:1:1 @url:3:5

for a testcase like this:

   try {
     new Function("throw new Error()")();
   } catch (e) {
     document.write(e.stack);
   }

-Boris