[wildcards] fix type parameter scope

Addresses a bunch of INVALID_ASSIGNMENT errors reported in the language and co19 tests.

CompileTimeError -> Pass (expected Pass)
language/wildcard_variables/non_binding/class_members_test
language/wildcard_variables/non_binding/top_level_function_test
language/wildcard_variables/non_binding/top_level_variable_test

MissingCompileTimeError -> Pass (expected Pass)
co19/LanguageFeatures/Wildcards/binding_A01_t08
co19/LanguageFeatures/Wildcards/binding_A01_t09

See: #55680

Change-Id: Ide4c3f3729a91d478be7a7e46477164e17703435
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/379442
Reviewed-by: Brian Wilkerson <[email protected]>
Commit-Queue: Phil Quitslund <[email protected]>

Author: pq

pkg/analyzer/lib/src/dart/element/scope.dart

@@ -604,7 +604,11 @@ class TypeParameterScope extends EnclosedScope {
     super.parent,
     List<TypeParameterElement> elements,
   ) {
-    elements.forEach(_addGetter);
+    for (var element in elements) {
+      if (!element.isWildcardVariable) {
+        _addGetter(element);
+      }
+    }
   }
 }
 

pkg/analyzer/test/src/dart/resolution/generic_function_type_test.dart

@@ -153,6 +153,18 @@ class C {
     return (_) {};
   }
 }
+''');
+  }
+
+  test_typeParameter_classScope_wildcards() async {
+    await assertNoErrorsInCode(r'''
+class C {
+  int _ = 0;
+
+  void m<_, _>() {
+    int _ = _;
+  }
+}
 ''');
   }
 }