[CodeComplete] Add an option to omit results from the preamble.
Summary:
Enumerating the contents of a namespace or global scope will omit any
decls that aren't already loaded, instead of deserializing them from the
PCH.
This allows a fast hybrid code completion where symbols from headers are
provided by an external index. (Sema already exposes the information
needed to do a reasonabl job of filtering them).
Clangd plans to implement this hybrid.
This option is just a hint - callers still need to postfilter results if
they want to *avoid* completing decls outside the main file.
Reviewers: bkramer, ilya-biryukov
Subscribers: cfe-commits
Differential Revision: https://reviews.llvm.org/D41989
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@322371
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