[msan] Origin tracking with history.

LLVM part of MSan implementation of advanced origin tracking,
when we record not only creation point, but all locations where
an uninitialized value was stored to memory, too.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@204151 91177308-0d34-0410-b5e6-96231b3b80d8