Merge pull request #26573 from davidungar/A-7-9-astscope-no-nesting

[NameLookup ASTScope] On-by-default.

Author: David Ungar

include/swift/Basic/LangOptions.h

@@ -246,7 +246,7 @@ namespace swift {
     /// Default is in \c ParseLangArgs
     ///
     /// This is a staging flag; eventually it will be removed.
-    bool EnableASTScopeLookup = false;
+    bool EnableASTScopeLookup = true;
 
     /// Someday, ASTScopeLookup will supplant lookup in the parser
     bool DisableParserLookup = false;

lib/AST/ASTScopeCreation.cpp

@@ -1750,7 +1750,7 @@ void ASTScopeImpl::reexpand(ScopeCreator &scopeCreator) {
   auto astAncestorScopes = rescueASTAncestorScopesForReuseFromMeOrDescendants();
   disownDescendants(scopeCreator);
   // If the expansion recurses back into the tree for lookup, the ASTAncestor
-  // scopes will have already been rescued and won't be found! HERE
+  // scopes will have already been rescued and won't be found!
   expandAndBeCurrent(scopeCreator);
   replaceASTAncestorScopes(astAncestorScopes);
 }