for WK1 Apple Mac-specific baselines and exceptions. 

This appears to come up from time to time (e.g., bug 106187 just now), where there is no good solution to indicate that a test will fail on WK1 and Lion WK2 but should work on newer versions of WK2.

Other ports (Gtk, Qt, Efl) have both -wk1 and -wk2 directories, but apple mac only uses -wk2. Adding a -wk1 directory would solve this problem.

However, the issue is complicated slightly by the fact that -- as things are currently implemented -- the easiest patch to do this would change the default location for new baselines from platform/mac-$version to platform/mac-wk1. Also, when generating new baselines with -2, we have that problem today (baselines go into mac-wk2 instead of platform/mac-$version).

It seems to me that using those directories by default is probably wrong, and I'm actually surprised this hasn't come up yet, but maybe baselines are more often generated w/ the -wk1 builds?

I could change the code to never use the -wk1 or -wk2 variants for baselines by default (and you'd have to manually specify a directory to use it), or I could change the code to leave -wk2 alone and just never use -wk1.

Or we could go whole-hog and create mac-$version-{wk1,wk2} dirs and use those as appropriate and rely on the baseline optimizer to de-dup things.

(Note that Gtk, Qt, Efl don't have this problem since they don't generally have version-specific dirs).

I have no real skin in this game, so I will implement whatever the apple folks want here.