Merge pull request #10641 from DougGregor/record-conformance-in-source-file-4.0jun23

[4.0jun23] [Type checker] Always record used conformances in the source file.

Author: DougGregor

lib/Sema/TypeCheckProtocol.cpp

@@ -5523,9 +5523,9 @@ void TypeChecker::markConformanceUsed(ProtocolConformanceRef conformance,
   auto normalConformance =
     conformance.getConcrete()->getRootNormalConformance();
 
-  if (normalConformance->isComplete()) return;
-
-  UsedConformances.insert(normalConformance);
+  // Make sure that the type checker completes this conformance.
+  if (normalConformance->isIncomplete())
+    UsedConformances.insert(normalConformance);
 
   // Record the usage of this conformance in the enclosing source
   // file.