Change isolate done-handler registry back to list instead of HashMap.

sdk/lib/_internal/compiler/js_lib/isolate_helper.dart

 // Copyright (c) 2012, 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 _isolate_helper;
 
 import 'dart:_js_embedded_names' show
     CLASS_ID_EXTRACTOR,
     CLASS_FIELDS_EXTRACTOR,
     CREATE_NEW_ISOLATE,
     CURRENT_SCRIPT,
     GLOBAL_FUNCTIONS,
     INITIALIZE_EMPTY_INSTANCE,
     INSTANCE_FROM_CLASS_ID;
 
 import 'dart:async';
-import 'dart:collection' show Queue, HashMap;
+import 'dart:collection' show Queue;
 import 'dart:isolate';
 import 'dart:_native_typed_data' show NativeByteBuffer, NativeTypedData;
 
 import 'dart:_js_helper' show
     Closure,
     InternalMap,
     Null,
     Primitives,
     convertDartClosureToJS,
     random64,
@@ skipping 322 matching lines @@
         _IsolateEvent event = delayedEvents.removeLast();
         _globalState.topEventLoop.prequeue(event);
       }
       isPaused = false;
     }
     _updateGlobalState();
   }
 
   void addDoneListener(SendPort responsePort, Object response) {
     if (doneHandlers == null) {
-      // TODO(lrn): Use map optimized for few keys.
-      doneHandlers = new HashMap();
+      doneHandlers = [];
     }
-    doneHandlers[responsePort] = response;
+    for (int i = 0; i < doneHandlers.length; i += 2) {
+      if (responsePort == doneHandlers[i]) {
+        doneHandlers[i + 1] = response;
+        return;
+      }
+    }
+    doneHandlers.add(responsePort);
+    doneHandlers.add(response);
   }
 
   void removeDoneListener(SendPort responsePort) {
     if (doneHandlers == null) return;
-    doneHandlers.remove(responsePort);
+    for (int i = 0; i < doneHandlers.length; i += 2) {
+      if (responsePort == doneHandlers[i]) {
+        doneHandlers.removeRange(i, i + 2);
+        return;
+      }
+    }
   }
 
   void setErrorsFatal(Capability authentification, bool errorsAreFatal) {
     if (terminateCapability != authentification) return;
     this.errorsAreFatal = errorsAreFatal;
   }
 
   void handlePing(SendPort responsePort, int pingType, Object response) {
     if (pingType == Isolate.IMMEDIATE ||
         (pingType == Isolate.BEFORE_NEXT_EVENT &&
@@ skipping 178 matching lines @@
     // we are listening on ourselves.
     // Closes all ports, including control port.
     for (var port in ports.values) {
       port._close();
     }
     ports.clear();
     weakPorts.clear();
     _globalState.isolates.remove(id); // indicate this isolate is not active
     errorPorts.clear();
     if (doneHandlers != null) {
-      doneHandlers.forEach((port, response) { port.send(response); });
+      for (int i = 0; i < doneHandlers.length; i += 2) {
+        SendPort responsePort = doneHandlers[i];
+        Object response = doneHandlers[i + 1];
+        responsePort.send(response);
+      }
       doneHandlers = null;
     }
   }
 
   /** Unregister a port on this isolate. */
   void unregister(int portId) {
     ports.remove(portId);
     weakPorts.remove(portId);
     _updateGlobalState();
   }
@@ skipping 858 matching lines @@
   }
 
   bool operator==(Object other) {
     if (identical(other, this)) return true;
     if (other is CapabilityImpl) {
       return identical(_id, other._id);
     }
     return false;
   }
 }