Error reporting for spans.

pkg/analyzer/lib/src/generated/error.dart

Index: pkg/analyzer/lib/src/generated/error.dart
diff --git a/pkg/analyzer/lib/src/generated/error.dart b/pkg/analyzer/lib/src/generated/error.dart
index 6b4d93efa9fd29bb73c54fd50c96a0b787efdb32..eac324c8dd64f251c560a84c8d3629437ca61241 100644
--- a/pkg/analyzer/lib/src/generated/error.dart
+++ b/pkg/analyzer/lib/src/generated/error.dart
@@ -6,6 +6,8 @@ library engine.error;
 
 import 'dart:collection';
 
+import 'package:source_span/source_span.dart';
+
 import 'ast.dart' show AstNode;
 import 'element.dart';
 import 'java_core.dart';
@@ -2663,6 +2665,15 @@ class ErrorReporter {
   }
 
   /**
+   * Report an error with the given [errorCode] and [arguments]. The location of
+   * the error is specified by the given [span].
+   */
+  void reportErrorForSpan(ErrorCode errorCode, SourceSpan span,
+      [List<Object> arguments]) {
+    reportErrorForOffset(errorCode, span.start.offset, span.length, arguments);
+  }
+
+  /**
    * Report an error with the given [errorCode] and [arguments]. The [token] is
    * used to compute the location of the error.
    */