Add FunctionEntity.asyncMarker and refactor SourceInformationStrategy to avoid ResolvedAst

pkg/compiler/lib/src/io/position_information.dart

 // Copyright (c) 2015, 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.
 
 /// Source information system mapping that attempts a semantic mapping between
 /// offsets of JavaScript code points to offsets of Dart code points.
 
 library dart2js.source_information.position;
 
 import '../common.dart';
 import '../elements/elements.dart'
-    show AstElement, ResolvedAst, ResolvedAstKind;
+    show AstElement, MemberElement, ResolvedAst, ResolvedAstKind;
 import '../js/js.dart' as js;
 import '../js/js_debug.dart';
 import '../js/js_source_mapping.dart';
 import '../tree/tree.dart' show Node, Send;
 import 'code_output.dart' show BufferedCodeOutput;
 import 'source_file.dart';
 import 'source_information.dart';
 
 /// [SourceInformation] that consists of an offset position into the source
 /// code.
@@ skipping 71 matching lines @@
       return _computeText('${closingPosition.sourceUri}');
     }
   }
 }
 
 class PositionSourceInformationStrategy
     implements JavaScriptSourceInformationStrategy {
   const PositionSourceInformationStrategy();
 
   @override
-  SourceInformationBuilder createBuilderForContext(ResolvedAst resolvedAst) {
-    return new PositionSourceInformationBuilder(resolvedAst);
+  SourceInformationBuilder createBuilderForContext(MemberElement member) {
+    return new PositionSourceInformationBuilder(member);
   }
 
   @override
   SourceInformationProcessor createProcessor(
       SourceMapperProvider provider, SourceInformationReader reader) {
     return new PositionSourceInformationProcessor(provider, reader);
   }
 
   @override
   void onComplete() {}
@@ skipping 21 matching lines @@
   @override
   SourceSpan get sourceSpan => new SourceSpan(null, null, null);
 }
 
 /// [SourceInformationBuilder] that generates [PositionSourceInformation].
 class PositionSourceInformationBuilder implements SourceInformationBuilder {
   final SourceFile sourceFile;
   final String name;
   final ResolvedAst resolvedAst;
 
-  PositionSourceInformationBuilder(ResolvedAst resolvedAst)
-      : this.resolvedAst = resolvedAst,
-        sourceFile = computeSourceFile(resolvedAst),
-        name = computeElementNameForSourceMaps(resolvedAst.element);
+  PositionSourceInformationBuilder(MemberElement member)
+      : this.resolvedAst = member.resolvedAst,
+        sourceFile = computeSourceFile(member.resolvedAst),
+        name = computeElementNameForSourceMaps(member.resolvedAst.element);
 
-  SourceInformation buildDeclaration(ResolvedAst resolvedAst) {
+  SourceInformation buildDeclaration(MemberElement member) {
+    ResolvedAst resolvedAst = member.resolvedAst;
     if (resolvedAst.kind != ResolvedAstKind.PARSED) {
       SourceSpan span = resolvedAst.element.sourcePosition;
       return new PositionSourceInformation(
           new OffsetSourceLocation(sourceFile, span.begin, name));
     } else {
       return new PositionSourceInformation(
           new OffsetSourceLocation(
               sourceFile, resolvedAst.node.getBeginToken().charOffset, name),
           new OffsetSourceLocation(
               sourceFile, resolvedAst.node.getEndToken().charOffset, name));
@@ skipping 80 matching lines @@
       Node body = resolvedAst.body;
       if (body != null) {
         return buildBegin(body);
       }
       // TODO(johnniwinther): Are there other cases?
     }
     return null;
   }
 
   @override
-  SourceInformationBuilder forContext(ResolvedAst resolvedAst) {
-    return new PositionSourceInformationBuilder(resolvedAst);
+  SourceInformationBuilder forContext(MemberElement member) {
+    return new PositionSourceInformationBuilder(member);
   }
 
   @override
   SourceInformation buildForeignCode(Node node) => buildBegin(node);
 
   @override
   SourceInformation buildStringInterpolation(Node node) => buildBegin(node);
 
   @override
   SourceInformation buildForInIterator(Node node) => buildBegin(node);
@@ skipping 1071 matching lines @@
 
   @override
   CodePosition operator [](js.Node node) {
     CodePosition codePosition = codePositions[node];
     if (codePosition == null) {
       coverage.registerNodesWithoutOffset(node);
     }
     return codePosition;
   }
 }