fix some bugs with next, back, and cancel in the profile manager. (#15223, #15271) re-write all callers of nsProfile::GetCurrentProfileDir() to use the file locator. (#15063) more profile code clean up. (#15042) rename the old 4.x history.dat file. it's called history.dat in 5.0, but the file formats are different. (binary in 4.x, vs mork in 5.0) git-svn-id: svn://10.0.0.236/trunk@49797 18797224-902f-48f8-a5cc-f745e15eee43