[BuilderTransform] NFC: Inline now redundant base class into ResultBuilderTransform

Author: xedin

Diff for: include/swift/Sema/ConstraintSystem.h

@@ -155,7 +155,7 @@ struct ResultBuilder {
   unsigned VarCounter = 0;
 
 public:
-  ResultBuilder(ConstraintSystem *CS, DeclContext *DC, Type builderType);
+  ResultBuilder(ConstraintSystem &CS, DeclContext *DC, Type builderType);
 
   DeclContext *getDeclContext() const { return DC; }