[dart2js] Remove old bug work around in collector.

Bug: http://dartbug.com/18175
Change-Id: Ife479c390e02d30a37a19288a381df9b3e4de958
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/155222
Commit-Queue: Joshua Litt <joshualitt@google.com>
Reviewed-by: Stephen Adams <sra@google.com>

Author: joshualitt

pkg/compiler/lib/src/js_emitter/program_builder/collector.dart

@@ -196,26 +196,6 @@ class Collector {
 
     neededClasses.addAll(classesOnlyNeededForRti);
 
-    // TODO(18175, floitsch): remove once issue 18175 is fixed.
-    if (neededClasses.contains(_commonElements.jsIntClass)) {
-      neededClasses.add(_commonElements.intClass);
-    }
-    if (neededClasses.contains(_commonElements.jsDoubleClass)) {
-      neededClasses.add(_commonElements.doubleClass);
-    }
-    if (neededClasses.contains(_commonElements.jsNumberClass)) {
-      neededClasses.add(_commonElements.numClass);
-    }
-    if (neededClasses.contains(_commonElements.jsStringClass)) {
-      neededClasses.add(_commonElements.stringClass);
-    }
-    if (neededClasses.contains(_commonElements.jsBoolClass)) {
-      neededClasses.add(_commonElements.boolClass);
-    }
-    if (neededClasses.contains(_commonElements.jsArrayClass)) {
-      neededClasses.add(_commonElements.listClass);
-    }
-
     // 4. Finally, sort the classes.
     List<ClassEntity> sortedClasses = _sorter.sortClasses(neededClasses);
 

tests/dart2js/18175_test.dart

@@ -0,0 +1,20 @@
+// Copyright (c) 2020, 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.
+
+import 'package:expect/expect.dart';
+
+class A implements B<C> {}
+
+class B<E> {}
+
+class C {}
+
+main() {
+  Expect.isFalse(A() is B<bool>);
+  Expect.isFalse(A() is B<int>);
+  Expect.isFalse(A() is B<num>);
+  Expect.isFalse(A() is B<double>);
+  Expect.isFalse(A() is B<String>);
+  Expect.isFalse(A() is B<List>);
+}