[CSDiag] NFC: Move findResolvedMemberRef to ConstraintSystem.cpp

This method is used by diagnostics and CSApply at this point.

Author: xedin

lib/Sema/CSDiag.cpp

@@ -2303,19 +2303,3 @@ void FailureDiagnosis::diagnoseAmbiguity(Expr *E) {
   diagnose(E->getLoc(), diag::type_of_expression_is_ambiguous)
     .highlight(E->getSourceRange());
 }
-
-/// If an UnresolvedDotExpr, SubscriptMember, etc has been resolved by the
-/// constraint system, return the decl that it references.
-ValueDecl *ConstraintSystem::findResolvedMemberRef(ConstraintLocator *locator) {
-  // See if we have a resolution for this member.
-  auto overload = findSelectedOverloadFor(locator);
-  if (!overload)
-    return nullptr;
-
-  // We only want to handle the simplest decl binding.
-  auto choice = overload->choice;
-  if (choice.getKind() != OverloadChoiceKind::Decl)
-    return nullptr;
-
-  return choice.getDecl();
-}

lib/Sema/ConstraintSystem.cpp

@@ -3940,3 +3940,19 @@ Expr *ConstraintSystem::buildAutoClosureExpr(Expr *expr,
   cacheExprTypes(result);
   return result;
 }
+
+/// If an UnresolvedDotExpr, SubscriptMember, etc has been resolved by the
+/// constraint system, return the decl that it references.
+ValueDecl *ConstraintSystem::findResolvedMemberRef(ConstraintLocator *locator) {
+  // See if we have a resolution for this member.
+  auto overload = findSelectedOverloadFor(locator);
+  if (!overload)
+    return nullptr;
+
+  // We only want to handle the simplest decl binding.
+  auto choice = overload->choice;
+  if (choice.getKind() != OverloadChoiceKind::Decl)
+    return nullptr;
+
+  return choice.getDecl();
+}