Add or Remove operation complete, and not while building the intermediate tree.
This trades a little bit more memory usage for less accesses to the FoldingSet. On a benchmark for the clang static analyzer, this shaves off another 13% of execution time when using field/array sensitivity.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@80955 91177308-0d34-0410-b5e6-96231b3b80d8