[dom] Make the DominatorTreeBase not a dynamic class!

Now that the passes are wrappers around this, we no longer need
a vtable, virtual destructor, and other associated mess. This is
particularly nice to me as this is a class template. =]

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@225970 91177308-0d34-0410-b5e6-96231b3b80d8
1 file changed