Introduce convenience methods into generated analysis server classes.

pkg/analysis_server/test/computer/error_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.computer.error;
 
 import 'package:analysis_server/src/computer/error.dart';
 import 'package:analysis_server/src/protocol2.dart';
 import 'package:analysis_server/src/constants.dart';
 import 'package:analysis_testing/mocks.dart';
@@ skipping 36 matching lines @@
     when(engineError.length).thenReturn(20);
   }
 
   void tearDown() {
     source = null;
     engineError = null;
   }
 
   void test_fromEngine_hasCorrection() {
     when(engineError.correction).thenReturn('my correction');
-    AnalysisError error = analysisErrorFromEngine(lineInfo, engineError);
+    AnalysisError error = new AnalysisError.fromEngine(lineInfo, engineError);
     expect(error.toJson(), {
       SEVERITY: 'ERROR',
       TYPE: 'COMPILE_TIME_ERROR',
       LOCATION: {
         FILE: 'foo.dart',
         OFFSET: 10,
         LENGTH: 20,
         START_LINE: 3,
         START_COLUMN: 2
       },
       MESSAGE: 'my message',
       CORRECTION: 'my correction'
     });
   }
 
   void test_fromEngine_noCorrection() {
     when(engineError.correction).thenReturn(null);
-    AnalysisError error = analysisErrorFromEngine(lineInfo, engineError);
+    AnalysisError error = new AnalysisError.fromEngine(lineInfo, engineError);
     expect(error.toJson(), {
       SEVERITY: 'ERROR',
       TYPE: 'COMPILE_TIME_ERROR',
       LOCATION: {
         FILE: 'foo.dart',
         OFFSET: 10,
         LENGTH: 20,
         START_LINE: 3,
         START_COLUMN: 2
       },
       MESSAGE: 'my message'
     });
   }
 
   void test_fromEngine_noLineInfo() {
     when(engineError.correction).thenReturn(null);
-    AnalysisError error = analysisErrorFromEngine(null, engineError);
+    AnalysisError error = new AnalysisError.fromEngine(null, engineError);
     expect(error.toJson(), {
       SEVERITY: 'ERROR',
       TYPE: 'COMPILE_TIME_ERROR',
       LOCATION: {
         FILE: 'foo.dart',
         OFFSET: 10,
         LENGTH: 20,
         START_LINE: -1,
         START_COLUMN: -1
       },
@@ skipping 40 matching lines @@
           'file': 'foo.dart',
           'offset': 10,
           'length': 20,
           'startLine': 3,
           'startColumn': 2
         },
         'message': 'my message'
       }]));
   }
 }