fixes #25094, type params in static methods shouldn't always be an error

pkg/analyzer/test/generated/resolver_test.dart

 // Copyright (c) 2014, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 library engine.resolver_test;
 
 import 'dart:collection';
 
 import 'package:analyzer/src/context/context.dart';
 import 'package:analyzer/src/generated/ast.dart';
@@ skipping 12725 matching lines @@
     FunctionElementImpl e = f.staticElement;
     expect(e.typeParameters.toString(), '[T]');
     expect(e.type.boundTypeParameters.toString(), '[T]');
     expect(e.type.typeParameters.toString(), '[]');
     expect(e.type.toString(), '<T>(T) → T');
 
     FunctionType ft = e.type.instantiate([typeProvider.stringType]);
     expect(ft.toString(), '(String) → String');
   }
 
+  void test_genericFunction_static() {
+    _resolveTestUnit(r'''
+class C<E> {
+  static /*=T*/ f/*<T>*/(/*=T*/ x) => null;
+}
+''');
+    SimpleIdentifier f = _findIdentifier('f');
+    MethodElementImpl e = f.staticElement;
+    expect(e.typeParameters.toString(), '[T]');
+    expect(e.type.boundTypeParameters.toString(), '[T]');
+    // TODO(jmesserly): we could get rid of this {E/E} substitution, but it's
+    // probably harmless, as E won't be used in the function (error verifier
+    // checks this), and {E/E} is a no-op anyway.
+    expect(e.type.typeParameters.toString(), '[E]');
+    expect(e.type.typeArguments.toString(), '[E]');
+    expect(e.type.toString(), '<T>(T) → T');
+
+    FunctionType ft = e.type.instantiate([typeProvider.stringType]);
+    expect(ft.toString(), '(String) → String');
+  }
+
   void test_genericFunction_typedef() {
     String code = r'''
 typedef T F<T>(T x);
 F f0;
 
 class C {
   static F f1;
   F f2;
   void g(F f3) {
     F f4;
@@ skipping 3170 matching lines @@
 
   void _resolveTestUnit(String code) {
     testCode = code;
     testSource = addSource(testCode);
     LibraryElement library = resolve2(testSource);
     assertNoErrors(testSource);
     verify([testSource]);
     testUnit = resolveCompilationUnit(testSource, library);
   }
 }