ListWrapper tweak.

editor/util/plugins/com.google.dart.java2dart/resources/java_core.dart

 library java.core;
 
 import "dart:math" as math;
 import "dart:uri";
 import "dart:collection" show ListBase;
 
 class JavaSystem {
   static int currentTimeMillis() {
     return (new DateTime.now()).millisecondsSinceEpoch;
   }
@@ skipping 293 matching lines @@
   }
 
   int lastIndexOf(E element, [int start]) {
     return elements.lastIndexOf(element, start);
   }
 
   void clear() {
     elements.clear();
   }
 
-  void remove(Object element) {
+  bool remove(Object element) {
     return elements.remove(element);
   }
 
   E removeAt(int index) {
     return elements.removeAt(index);
   }
 
   E removeLast() {
     return elements.removeLast();
   }
@@ skipping 115 matching lines @@
       }
     } else if (sb.length > newLength) {
       var s = sb.toString().substring(0, newLength);
       sb = new StringBuffer(s);
     }
   }
   void clear() {
     sb = new StringBuffer();
   }
 }