Merge pull request #5566 from jeffreymorlan/fix5444

Fix issue #5444

src/compiler/checker.ts

@@ -11439,7 +11439,9 @@ namespace ts {
                         seen = c === node;
                     }
                 });
-                if (subsequentNode) {
+                // We may be here because of some extra junk between overloads that could not be parsed into a valid node.
+                // In this case the subsequent node is not really consecutive (.pos !== node.end), and we must ignore it here.
+                if (subsequentNode && subsequentNode.pos === node.end) {
                     if (subsequentNode.kind === node.kind) {
                         const errorNode: Node = (<FunctionLikeDeclaration>subsequentNode).name || subsequentNode;
                         // TODO(jfreeman): These are methods, so handle computed name case