This adds all the patches that were applied in the past to the
clang700-import branch, under contrib/llvm. After these, there only
minimal diffs left between the port sources and the base sources.
Most of these remaining diffs are due to #ifdef shortcuts in the base
sources, because we don't compile certain features in. Other diffs are
because the port has applied a few changes that we don't have in base.
The list of PRs that were affected by the added patches is:
PR: 212343, 230604
I will also put this in the eventual commit message.