Release notes for SPI MacroExpansion/PluginMessageHandling

Author: rintaro

Release Notes/511.md

@@ -116,7 +116,11 @@
   - Description: The new property provides the lexical context in which the macro is expanded, and has several paired API changes. Types that conform to `MacroExpansionContext` will need to implement this property. Additionally, the `HostToPluginMessage` cases `expandFreestandingMacro` and `expandAttachedMacro` now include an optional `lexicalContext`. Finally, the `SyntaxProtocol.expand(macros:in:indentationWidth:)` syntactic expansion operation has been deprecated in favor of a new version `expand(macros:contextGenerator:indentationWidth:)` that takes a function produces a new macro expansion context for each expansion.
   - Pull request: https://github.com/apple/swift-syntax/pull/1554
   - Migration steps: Add the new property `lexicalContext` to any `MacroExpansionContext`-conforming types. If implementing the host-to-plugin message protocol, add support for `lexicalContext`. For macro expansion operations going through `SyntaxProtocol.expand`, provide a context generator that creates a fresh context including the lexical context.
-  
+
+- All symbols in `SwiftSyntaxMacroExpansion` and `SwiftCompilerPluginMessageHandling` are now SPI
+  - Description: These modules are only intended to be used from some internal components. Any other modules should not use them directly.
+  - Pull requrest: https://github.com/apple/swift-syntax/pull/2489
+  - Micration staps: Stop using these modules.
 
 ## Template