Prototype re-compiling methods in dart2js

lib/compiler/implementation/enqueue.dart

Index: lib/compiler/implementation/enqueue.dart
diff --git a/lib/compiler/implementation/enqueue.dart b/lib/compiler/implementation/enqueue.dart
index 855c539fa1d4a28b9b0a875062deca3965ceb5cf..880da61e67927f02bcd6b40d1409e06afb41565a 100644
--- a/lib/compiler/implementation/enqueue.dart
+++ b/lib/compiler/implementation/enqueue.dart
@@ -17,12 +17,41 @@ class EnqueueTask extends CompilerTask {
   }
 }
 
+class RecompilationQueue {
+  final Queue<WorkItem> queue;
+  final Set<Element> queueElements;
+
+  RecompilationQueue()
+    : queue = new Queue<WorkItem>(),
+      queueElements = new Set<Element>();
+
+  void add(Element element, [TreeElements elements]) {
+    if (queueElements.contains(element)) return;
+    if (element.kind !== ElementKind.GENERATIVE_CONSTRUCTOR_BODY &&
+        element.kind !== ElementKind.GENERATIVE_CONSTRUCTOR) {
+      queueElements.add(element);
+      queue.add(new WorkItem(element, elements));
+    }
+  }
+
+  int get length() => queue.length;
+
+  bool isEmpty() => queue.isEmpty();
+
+  WorkItem next() {
+    WorkItem item = queue.removeLast();
+    queueElements.remove(item.element);
+    return item;
+  }
+}
+
 class Enqueuer {
   final Compiler compiler; // TODO(ahe): Remove this dependency.
   final Map<String, Link<Element>> instanceMembersByName;
   final Set<ClassElement> seenClasses;
   final Universe universe;
   final Queue<WorkItem> queue;
+  final RecompilationQueue recompilationCandidates;
   bool queueIsClosed = false;
   EnqueueTask task;
 
@@ -30,9 +59,11 @@ class Enqueuer {
     : instanceMembersByName = new Map<String, Link<Element>>(),
       seenClasses = new Set<ClassElement>(),
       universe = new Universe(),
-      queue = new Queue<WorkItem>();
+      queue = new Queue<WorkItem>(),
+      recompilationCandidates = new RecompilationQueue();
 
   void addToWorkList(Element element, [TreeElements elements]) {
+    if (compiler.pass == 2) return;
     if (queueIsClosed) {
       compiler.internalErrorOnElement(element, "Work list is closed.");
     }
@@ -42,6 +73,13 @@ class Enqueuer {
     queue.add(new WorkItem(element, elements));
   }
 
+  void addToRecompilationCandidates(Element element, [TreeElements elements]) {
+    if (queueIsClosed) {
+      compiler.internalErrorOnElement(element, "Work list is closed.");
+    }
+    recompilationCandidates.add(element, elements);
+  }
+
   void registerInstantiatedClass(ClassElement cls) {
     universe.instantiatedClasses.add(cls);
     onRegisterInstantiatedClass(cls);