This reverts commit e9dedf3c27.
The revert is required as foreign reference types are available for SwiftStdlib 5.8 and above, but the Swift compiler
sources back deploy to older stdlibs as well.
This also removes `BridgedDiagnosticArgumentKind` in favor of `swift::DiagnosticArgumentKind`, bringing us one step closer to bridging the entire diagnostic engine via C++ interop.
rdar://83361087
C++ interop is now enabled in SwiftCompilerSources, so we can remove some of the C bridging layer and use C++ classes directly from Swift.
rdar://83361087
This fixes:
* An issue where the diagnostic messages were leaked
* Diagnose at correct position inside the regex literal
To do this:
* Introduce 'Parse' SwiftCompiler module that is a bridging layer
between '_CompilerRegexParser' and C++ libParse
* Move libswiftParseRegexLiteral and libswiftLexRegexLiteral to 'Parse'
Also this change makes 'SwiftCompilerSources/Package.swift' be configured
by CMake so it can actually be built with 'swift-build'.
rdar://92187284