Shuffle APIs around a little bit, so that if you pass custom summary options,...

Shuffle APIs around a little bit, so that if you pass custom summary options, we don't end up caching the summary hence obtained. You may want to obtain an uncapped summary, but this should not be reflected in the summary we cache. The drawback is that we don't cache as aggressively as we could, but at least you get to have different summaries with different options without having to reset formatters or the SBValue at each step

llvm-svn: 222280