Add support for fields to the new dart backend.

pkg/compiler/lib/src/cps_ir/cps_ir_tracer.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 dart2js.ir_tracer;
 
 import 'dart:async' show EventSink;
 
 import 'cps_ir_nodes.dart' as cps_ir hide Function;
 import '../tracer.dart';
 
 /**
  * If true, show LetCont expressions in output.
  */
 const bool IR_TRACE_LET_CONT = false;
 
 class IRTracer extends TracerUtil implements cps_ir.Visitor {
   EventSink<String> output;
 
   IRTracer(this.output);
 
   visit(cps_ir.Node node) => node.accept(this);
 
-  void traceGraph(String name, cps_ir.FunctionDefinition graph) {
+  void traceGraph(String name, cps_ir.ExecutableDefinition graph) {
     tag("cfg", () {
       printProperty("name", name);
-      visitFunctionDefinition(graph);
+      visit(graph);
     });
   }
 
   // Temporary field used during tree walk
   Names names;
 
-  visitFunctionDefinition(cps_ir.FunctionDefinition f) {
+  visitExecutableDefinition(cps_ir.ExecutableDefinition node) {
     names = new Names();
     BlockCollector builder = new BlockCollector(names);
-    builder.visit(f);
+    builder.visit(node);
 
     printNode(builder.entry);
     for (Block block in builder.cont2block.values) {
       printNode(block);
     }
     names = null;
   }
 
+  visitFieldDefinition(cps_ir.FieldDefinition node) {
+    visitExecutableDefinition(node);
+  }
+
+  visitFunctionDefinition(cps_ir.FunctionDefinition node) {
+    visitExecutableDefinition(node);
+  }
+
   int countUses(cps_ir.Definition definition) {
     int count = 0;
     cps_ir.Reference ref = definition.firstRef;
     while (ref != null) {
       ++count;
       ref = ref.next;
     }
     return count;
   }
 
@@ skipping 266 matching lines @@
 
   Block getBlock(cps_ir.Continuation c) {
     Block block = cont2block[c];
     if (block == null) {
       block = new Block(names.name(c), c.parameters, c.body);
       cont2block[c] = block;
     }
     return block;
   }
 
-  visitFunctionDefinition(cps_ir.FunctionDefinition f) {
-    entry = current_block = new Block(names.name(f), [], f.body);
-    visit(f.body);
+  visitExecutableDefinition(cps_ir.ExecutableDefinition node) {
+    entry = current_block = new Block(names.name(node), [], node.body);
+    visit(node.body);
+  }
+
+  visitFieldDefinition(cps_ir.FieldDefinition node) {
+    visitExecutableDefinition(node);
+  }
+
+  visitFunctionDefinition(cps_ir.FunctionDefinition node) {
+    visitExecutableDefinition(node);
   }
 
   visitLetPrim(cps_ir.LetPrim exp) {
     visit(exp.body);
   }
 
   visitLetCont(cps_ir.LetCont exp) {
     visit(exp.continuation);
     visit(exp.body);
   }
@@ skipping 44 matching lines @@
     }
   }
 
   visitContinuation(cps_ir.Continuation c) {
     var old_node = current_block;
     current_block = getBlock(c);
     visit(c.body);
     current_block = old_node;
   }
 }