Do not treat elements of lists allocated through new List() and new List.filled() as potentially nu…

sdk/lib/_internal/compiler/implementation/compiler.dart

Index: sdk/lib/_internal/compiler/implementation/compiler.dart
===================================================================
--- sdk/lib/_internal/compiler/implementation/compiler.dart	(revision 24172)
+++ sdk/lib/_internal/compiler/implementation/compiler.dart	(working copy)
@@ -760,6 +760,15 @@
         listClass.lookupConstructor(callConstructor);
   }
 
+  Element _filledListConstructor;
+  Element get filledListConstructor {
+    if (_filledListConstructor != null) return _filledListConstructor;
+    Selector callConstructor = new Selector.callConstructor(
+        const SourceString("filled"), listClass.getLibrary());
+    return _filledListConstructor =
+        listClass.lookupConstructor(callConstructor);
+  }
+
   void scanBuiltinLibraries() {
     jsHelperLibrary = scanBuiltinLibrary('_js_helper');
     interceptorsLibrary = scanBuiltinLibrary('_interceptors');