Move FutureImpl and CompleterImpl from coreimpl to core, while also making them private.

lib/core/future_impl.dart

Index: lib/core/future_impl.dart
diff --git a/lib/coreimpl/future_implementation.dart b/lib/core/future_impl.dart
similarity index 93%
rename from lib/coreimpl/future_implementation.dart
rename to lib/core/future_impl.dart
index 8e1efd0ed858fa56007148cb01b4de488fb8553b..bbae82d1667ffaff49b056c537143ee23b10d050 100644
--- a/lib/coreimpl/future_implementation.dart
+++ b/lib/core/future_impl.dart
@@ -1,7 +1,7 @@
 // Copyright 2012 Google Inc. All Rights Reserved.
 // Dart core library.
 
-class FutureImpl<T> implements Future<T> {
+class _FutureImpl<T> implements Future<T> {
 
   bool _isComplete = false;
 
@@ -41,13 +41,13 @@ class FutureImpl<T> implements Future<T> {
    */
   final List<Function> _completionListeners;
 
-  FutureImpl()
+  _FutureImpl()
     : _successListeners = [],
       _exceptionHandlers = [],
       _completionListeners = [];
 
-  factory FutureImpl.immediate(T value) {
-    final res = new FutureImpl();
+  factory _FutureImpl.immediate(T value) {
+    final res = new _FutureImpl();
     res._setValue(value);
     return res;
   }
@@ -56,7 +56,7 @@ class FutureImpl<T> implements Future<T> {
     if (!isComplete) {
       throw new FutureNotCompleteException();
     }
-    if (_exception !== null) {
+    if (_exception != null) {
       throw new FutureUnhandledException(_exception, stackTrace);
     }
     return _value;
@@ -81,7 +81,7 @@ class FutureImpl<T> implements Future<T> {
   }
 
   bool get hasValue {
-    return isComplete && _exception === null;
+    return isComplete && _exception == null;
   }
 
   void then(void onSuccess(T value)) {
@@ -119,7 +119,7 @@ class FutureImpl<T> implements Future<T> {
     _isComplete = true;
 
     try {
-      if (_exception !== null) {
+      if (_exception != null) {
         for (Function handler in _exceptionHandlers) {
           // Explicitly check for true here so that if the handler returns null,
           // we don't get an exception in checked mode.
@@ -157,7 +157,7 @@ class FutureImpl<T> implements Future<T> {
   }
 
   void _setException(Object exception, Object stackTrace) {
-    if (exception === null) {
+    if (exception == null) {
       // null is not a legal value for the exception of a Future.
       throw new ArgumentError(null);
     }
@@ -250,11 +250,11 @@ class FutureImpl<T> implements Future<T> {
   }
 }
 
-class CompleterImpl<T> implements Completer<T> {
+class _CompleterImpl<T> implements Completer<T> {
 
-  final FutureImpl<T> _futureImpl;
+  final _FutureImpl<T> _futureImpl;
 
-  CompleterImpl() : _futureImpl = new FutureImpl() {}
+  _CompleterImpl() : _futureImpl = new _FutureImpl() {}
 
   Future<T> get future {
     return _futureImpl;
@@ -268,3 +268,4 @@ class CompleterImpl<T> implements Completer<T> {
     _futureImpl._setException(exception, stackTrace);
   }
 }
+