Harmles tweak in VG_(record_startup_wd) to not allocate too much
memory.


git-svn-id: svn://svn.valgrind.org/valgrind/branches/BUF_REMOVAL@14207 a5019735-40e9-0310-863c-91ae7b9d1cf9
In read_dot_valgrindrc use a large enough buffer allocated on the
stack. 
Also assert that the passed in directory is not NULL. This is 
true at all call sites. The old code would have attempted to read
/.valgrindrc for dir == NULL and I don't think we want that.


git-svn-id: svn://svn.valgrind.org/valgrind/branches/BUF_REMOVAL@14208 a5019735-40e9-0310-863c-91ae7b9d1cf9
In VG_(redir_notify_new_DebugInfo) use a large enough buffer
allocated on the stack.


git-svn-id: svn://svn.valgrind.org/valgrind/branches/BUF_REMOVAL@14209 a5019735-40e9-0310-863c-91ae7b9d1cf9