[CursorInfo] Add ObjC location to generated symbol graph

[bnbarham]

Add the file for an imported ObjC-symbol to the generated symbol graph
when ObjC documentation is requested.

Skips line/column information for now since it's not needed. If we add
those we should extract location retrieval to a common method for both
cursor info and symbol graph gen.

Resolves rdar://91658873.

[bnbarham]

@swift-ci please test

[bnbarham]

@QuietMisdreavus is there any way to pass those symbol graph options down from symbolgraph-extract? I was thinking it'd probably be better to move these tests into SymbolGraph and then have cursor info just test the very basics. Can do that in a later PR though.

[QuietMisdreavus]

@bnbarham If you want to set an option directly in swift-symbolgraph-extract, you'll need to add a CLI flag for it. There's a section of symbol-graph-specific options in Options.td, so you should be able to add one there and load it just in swift_symbolgraph_extract_main.cpp.

[bnbarham]

@bnbarham If you want to set an option directly in swift-symbolgraph-extract, you'll need to add a CLI flag for it. There's a section of symbol-graph-specific options in Options.td, so you should be able to add one there and load it just in swift_symbolgraph_extract_main.cpp.

Ah nice, thanks! I'll refactor those tests in a separate PR later.

[QuietMisdreavus]

This looks great, thanks!

[ethan-kusters]

Thank you!

[bnbarham]

@swift-ci please test macOS platform