Merge 14206,14207,14261,14577,14578 from BUF_REMOVAL branch to trunk.
This changes VG_(record_startup_wd) to dynamically allocate a large
enough buffer for the directory name. As the dynamic memory manager has
started up a while ago, this is quite safe. Also rewrite VG_(get_startup_wd)
to simply return the directory name. No more messing with copying it
around. Adapt call sites.


git-svn-id: svn://svn.valgrind.org/valgrind/trunk@14579 a5019735-40e9-0310-863c-91ae7b9d1cf9