Add navigation region for 'library' directives.

pkg/analysis_server/test/analysis/notification_navigation_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 test.analysis.notification.navigation;
 
 import 'dart:async';
 
 import 'package:analysis_server/src/constants.dart';
 import 'package:analysis_server/src/protocol.dart';
@@ skipping 85 matching lines @@
    */
   void assertHasTarget(String search, [int length = -1]) {
     int offset = findOffset(search);
     if (length == -1) {
       length = findIdentifierLength(search);
     }
     assertHasFileTarget(testFile, offset, length);
   }
 
   /**
+   * Validates that there is a target in [testTargets]  with [testFile], at the
+   * offset of [str] in [testFile], and with the length of  [str].
+   */
+  void assertHasTargetString(String str) {
+    assertHasTarget(str, str.length);
+  }
+
+  /**
    * Validates that there is no a region at [search] and with the given
    * [length].
    */
   void assertNoRegion(String search, int length) {
     int offset = findOffset(search);
     findRegion(offset, length, false);
   }
 
   /**
    * Validates that there is no a region at [search] with any length.
@@ skipping 458 matching lines @@
         assertHasRegionString('B<A>();', 'B'.length);
         assertHasTarget('B() {}', 0);
       }
       {
         assertHasRegion('A>();');
         assertHasTarget('A {');
       }
     });
   }
 
+  test_library() {
+    addTestFile('''
+library my.lib;
+''');
+    return prepareNavigation().then((_) {
+      assertHasRegionString('my.lib');
+      assertHasTargetString('my.lib');
+    });
+  }
+
   test_multiplyDefinedElement() {
     addFile('$projectPath/bin/libA.dart', 'library A; int TEST = 1;');
     addFile('$projectPath/bin/libB.dart', 'library B; int TEST = 2;');
     addTestFile('''
 import 'libA.dart';
 import 'libB.dart';
 main() {
   TEST;
 }
 ''');
@@ skipping 205 matching lines @@
   test_type_void() {
     addTestFile('''
 void main() {
 }
 ''');
     return prepareNavigation().then((_) {
       assertNoRegionAt('void');
     });
   }
 }