No more warnings for duplicate unnamed lib imports.

pkg/analyzer/test/generated/static_warning_code_test.dart

Index: pkg/analyzer/test/generated/static_warning_code_test.dart
diff --git a/pkg/analyzer/test/generated/static_warning_code_test.dart b/pkg/analyzer/test/generated/static_warning_code_test.dart
index a5b0555a77ec42eb42ee3778c8a7a59f2110fd4f..3d63d3caa8f1d8e9fd68e2565250af0db87d1856 100644
--- a/pkg/analyzer/test/generated/static_warning_code_test.dart
+++ b/pkg/analyzer/test/generated/static_warning_code_test.dart
@@ -1264,18 +1264,6 @@ export 'lib2.dart';''');
     verify([source]);
   }
 
-  void test_exportDuplicatedLibraryUnnamed() {
-    Source source = addSource(r'''
-library test;
-export 'lib1.dart';
-export 'lib2.dart';''');
-    addNamedSource("/lib1.dart", "");
-    addNamedSource("/lib2.dart", "");
-    computeLibrarySourceErrors(source);
-    assertErrors(source, [StaticWarningCode.EXPORT_DUPLICATED_LIBRARY_UNNAMED]);
-    verify([source]);
-  }
-
   void test_extraPositionalArguments() {
     Source source = addSource(r'''
 f() {}
@@ -1488,22 +1476,6 @@ import 'lib2.dart';''');
     verify([source]);
   }
 
-  void test_importDuplicatedLibraryUnnamed() {
-    Source source = addSource(r'''
-library test;
-import 'lib1.dart';
-import 'lib2.dart';''');
-    addNamedSource("/lib1.dart", "");
-    addNamedSource("/lib2.dart", "");
-    computeLibrarySourceErrors(source);
-    assertErrors(source, [
-      StaticWarningCode.IMPORT_DUPLICATED_LIBRARY_UNNAMED,
-      HintCode.UNUSED_IMPORT,
-      HintCode.UNUSED_IMPORT
-    ]);
-    verify([source]);
-  }
-
   void test_importOfNonLibrary() {
     resolveWithErrors(<String>[
       r'''