XP_MAC GC leak detector changes:  using LMGetCurStackBase to compute stack bottom, and considering all threads GCable. r=sdagley (checking in for beard). bug=15906
XP_MAC GC leak detector changes:  using LMGetCurStackBase to compute stack bottom, and considering all threads GCable. r=sdagley (checking in for beard). bug=15906

thespooler/nspr,thespooler/nspr,thespooler/nspr,thespooler/nspr,thespooler/nspr