[DAS] Fixes "Go to declaration" for undefined new constructor

Fixes: #60773
Change-Id: I7ee7cec371fbf0d0f9de1a4fe2b946929ba80d61
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/432741
Reviewed-by: Brian Wilkerson <[email protected]>
Reviewed-by: Samuel Rawlins <[email protected]>
Commit-Queue: Brian Wilkerson <[email protected]>
Auto-Submit: Felipe Morschel <[email protected]>

Author: FMorschel

pkg/analysis_server/test/lsp/definition_test.dart

@@ -1099,6 +1099,21 @@ class [!A!] {}
     await testContents(contents);
   }
 
+  Future<void> test_unexisting_implicit_new_constructor() async {
+    var contents = '''
+class [!A!] {
+  A.constructor();
+}
+
+void f() {
+  // ignore: new_with_undefined_constructor_default
+  A^();
+}
+''';
+
+    await testContents(contents);
+  }
+
   Future<void> test_unopenFile() async {
     var contents = '''
 [!foo!]() {

pkg/analyzer_plugin/lib/src/utilities/navigation/navigation_dart.dart

@@ -454,6 +454,17 @@ class _DartNavigationComputerVisitor extends RecursiveAstVisitor<void> {
     computer._addRegionForElement(node.rightBracket, element);
   }
 
+  @override
+  void visitInstanceCreationExpression(InstanceCreationExpression node) {
+    if (node.constructorName.element == null) {
+      computer._addRegionForElement(
+        node.constructorName,
+        node.constructorName.type.element2,
+      );
+    }
+    super.visitInstanceCreationExpression(node);
+  }
+
   @override
   void visitLibraryDirective(LibraryDirective node) {
     computer._addRegionForElement(node.name2, node.element2);