Fix PR4922, where Sema would complete tentative definitions in nondeterminstic
order because it was doing so while iterating over a densemap.

There are still similar problems in other places, for example 
WeakUndeclaredIdentifiers is still written to the PCH file in a nondeterminstic
order, and we emit warnings about #pragma weak in nondeterminstic order.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@81236 91177308-0d34-0410-b5e6-96231b3b80d8
5 files changed