[ConstraintSystem] Move getResolvedOverloads() from CSStep to ConstraintSystem.

Author: hborla

include/swift/Sema/ConstraintSystem.h

@@ -5300,6 +5300,12 @@ class ConstraintSystem {
                             SmallVectorImpl<unsigned> &Ordering,
                             SmallVectorImpl<unsigned> &PartitionBeginning);
 
+  /// The overload sets that have already been resolved along the current path.
+  const llvm::MapVector<ConstraintLocator *, SelectedOverload> &
+  getResolvedOverloads() const {
+    return ResolvedOverloads;
+  }
+
   /// If we aren't certain that we've emitted a diagnostic, emit a fallback
   /// diagnostic.
   void maybeProduceFallbackDiagnostic(SolutionApplicationTarget target) const;

lib/Sema/CSStep.h

@@ -213,11 +213,6 @@ class SolverStep {
     CS.CG.addConstraint(constraint);
   }
 
-  const llvm::MapVector<ConstraintLocator *, SelectedOverload> &
-  getResolvedOverloads() const {
-    return CS.ResolvedOverloads;
-  }
-
   void recordDisjunctionChoice(ConstraintLocator *disjunctionLocator,
                                unsigned index) const {
     CS.recordDisjunctionChoice(disjunctionLocator, index);