Fix incremental resolution when inserting/removing empty lines before comments.

pkg/analyzer/test/generated/incremental_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 analyzer.test.generated.incremental_resolver_test;
 
 import 'package:analyzer/dart/ast/ast.dart';
 import 'package:analyzer/dart/ast/token.dart';
 import 'package:analyzer/dart/element/element.dart';
 import 'package:analyzer/src/context/cache.dart';
@@ skipping 1330 matching lines @@
 ''');
     _updateAndValidate(r'''
 class A {
   a() {}
 
   b() {}
 }
 ''');
   }
 
+  void test_true_emptyLine_betweenClassMembers_insert_beforeComment() {
+    _resolveUnit(r'''
+class A {
+  a() {}
+  /// BBB
+  b() {}
+}
+''');
+    _updateAndValidate(r'''
+class A {
+  a() {}
+
+  /// BBB
+  b() {}
+}
+''');
+  }
+
   void test_true_emptyLine_betweenClassMembers_remove() {
     _resolveUnit(r'''
 class A {
   a() {}
 
   b() {}
 }
 ''');
     _updateAndValidate(r'''
 class A {
   a() {}
   b() {}
 }
 ''');
   }
 
-  void test_true_emptyLine_betweenCompilationUnitMembers_insert() {
+  void test_true_emptyLine_betweenClassMembers_remove_beforeComment() {
+    _resolveUnit(r'''
+class A {
+  a() {}
+
+  /// BBB
+  b() {}
+}
+''');
+    _updateAndValidate(r'''
+class A {
+  a() {}
+  /// BBB
+  b() {}
+}
+''');
+  }
+
+  void test_true_emptyLine_betweenUnitMembers_insert() {
     _resolveUnit(r'''
 a() {}
 b() {}
 ''');
     _updateAndValidate(r'''
 a() {}
 
 b() {}
 ''');
   }
 
-  void test_true_emptyLine_betweenCompilationUnitMembers_remove() {
+  void test_true_emptyLine_betweenUnitMembers_insert_beforeComment() {
+    _resolveUnit(r'''
+a() {}
+
+// BBB
+b() {}
+''');
+    _updateAndValidate(r'''
+a() {}
+
+
+// BBB
+b() {}
+''');
+  }
+
+  void test_true_emptyLine_betweenUnitMembers_remove() {
     _resolveUnit(r'''
 a() {
   print(1)
 }
 
 b() {
   foo(42);
 }
 foo(String p) {}
 ''');
     _updateAndValidate(r'''
 a() {
   print(1)
 }
 b() {
   foo(42);
 }
 foo(String p) {}
 ''');
   }
 
+  void test_true_emptyLine_betweenUnitMembers_remove_beforeComment() {
+    _resolveUnit(r'''
+a() {}
+
+// BBB
+b() {}
+''');
+    _updateAndValidate(r'''
+a() {}
+// BBB
+b() {}
+''');
+  }
+
   void test_true_todoHint() {
     _resolveUnit(r'''
 main() {
   print(1);
 }
 foo() {
  // TODO
 }
 ''');
     List<AnalysisError> oldErrors = analysisContext.computeErrors(source);
@@ skipping 857 matching lines @@
   void logException(Object exception, [Object stackTrace]) {
     lastException = exception;
     lastStackTrace = stackTrace;
   }
 
   @override
   logging.LoggingTimer startTimer() {
     return new logging.LoggingTimer(this);
   }
 }