Previously, `type lookup` for types in namespaces didn't work with the
native PDB plugin, because `FindTypes` would only look for types whose
base name was equal to their full name. PDB/CodeView does not store the
base names in the TPI stream, but the types have their full name (e.g.
`std::thread` instead of `thread`). So `findRecordsByName` would only
return types in the top level namespace.
This PR changes the lookup to go through all types and check their base
name. As that could be a bit expensive, the names are first cached
(similar to the function lookup in the DIA PDB plugin). Potential types
are checked with `TypeQuery::ContextMatches`.
To be able to handle anonymous namespaces, I changed
`TypeQuery::ContextMatches`. The [`TypeQuery`
constructor](9ad7edef42/lldb/source/Symbol/Type.cpp (L76-L79))
inserts all name components as `CompilerContextKind::AnyDeclContext`. To
skip over anonymous namespaces, `ContextMatches` checked if a component
was empty and exactly of kind `Namespace`. For our query, the last check
was always false, so we never skipped anonymous namespaces. DWARF
doesn't have this problem, as it [constructs the context
outside](abe93d9d7e/lldb/source/Plugins/SymbolFile/DWARF/DWARFIndex.cpp (L154-L160))
and has proper information about namespaces. I'm not fully sure if my
change is correct and that it doesn't break other users of `TypeQuery`.
This enables `type lookup <type>` to work on types in namespaces.
However, expressions don't work with this yet, because `FindNamespace`
is unimplemented for native PDB.