Compute source spans for IR nodes and J/K-elements

pkg/compiler/lib/src/resolution/resolution_strategy.dart

 // Copyright (c) 2017, 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 dart2js.resolution_strategy;
 
 import 'package:front_end/src/fasta/scanner.dart' show Token;
 
 import '../common.dart';
 import '../common_elements.dart';
@@ skipping 28 matching lines @@
 import '../patch_parser.dart';
 import '../resolved_uri_translator.dart';
 import '../universe/call_structure.dart';
 import '../universe/use.dart';
 import '../universe/world_builder.dart';
 import '../universe/world_impact.dart';
 import 'no_such_method_resolver.dart';
 
 /// [FrontendStrategy] that loads '.dart' files and creates a resolved element
 /// model using the resolver.
-class ResolutionFrontEndStrategy extends FrontendStrategyBase {
+class ResolutionFrontEndStrategy extends FrontendStrategyBase
+    with ComputeSpannableMixin {
   final Compiler _compiler;
   final _CompilerElementEnvironment _elementEnvironment;
   final CommonElements commonElements;
 
   AnnotationProcessor _annotationProcessor;
 
   factory ResolutionFrontEndStrategy(Compiler compiler) {
     ElementEnvironment elementEnvironment =
         new _CompilerElementEnvironment(compiler);
     CommonElements commonElements = new CommonElements(elementEnvironment);
@@ skipping 155 matching lines @@
           errorElement.messageKind, errorElement.messageArguments);
     }
     MethodElement mainMethod;
     if (mainFunction != null && !mainFunction.isMalformed) {
       mainFunction.computeType(_compiler.resolution);
       mainMethod = mainFunction;
     }
     _elementEnvironment._mainFunction = mainMethod;
     return mainMethod;
   }
+}
 
+class ComputeSpannableMixin {
   SourceSpan spanFromToken(Element currentElement, Token token) =>
       _spanFromTokens(currentElement, token, token);
 
   SourceSpan _spanFromTokens(Element currentElement, Token begin, Token end,
       [Uri uri]) {
     if (begin == null || end == null) {
       // TODO(ahe): We can almost always do better. Often it is only
       // end that is null. Otherwise, we probably know the current
       // URI.
       throw 'Cannot find tokens to produce error message.';
@@ skipping 636 matching lines @@
   @override
   WorkItem createWorkItem(MemberElement element) {
     assert(element.isDeclaration, failedAt(element));
     if (element.isMalformed) return null;
 
     assert(element is AnalyzableElement,
         failedAt(element, 'Element $element is not analyzable.'));
     return _resolution.createWorkItem(element);
   }
 }