Retrieving local rename ranges and the local rename refactoring both had
almost identical methods, except for the addition of retrieving the
outermost shadowed decl that was added a couple months back. Merge them.
Resolves rdar://106529370.
This adds a new `primary_file` key, which defaults to `sourcefile`. For
nested expansions, `primary_file` should be set to the containing file
and `sourcefile` to the name of the macro expansion buffer.
This allows us to model the `ResolvedCursorInfo` types as a proper type hierarchy instead of having to store all values in the base `ResolvedCursorInfo` type.
rdar://102853071
IDE/Refactoring had dependencies to libswiftIndex, but libswiftIndex
also depends on libswiftIDE (SourceEntityWalker, etc.)
To break libswiftIndex <-> libswiftIDE dependency cycle, move
"refactoring" related files to a new library 'libswiftRefactoring'
rdar://101692282
