If Color constructor is passed a value > 0xFFFFFFFF, Sky crashes

sky/engine/core/painting/Color.dart

Index: sky/engine/core/painting/Color.dart
diff --git a/sky/engine/core/painting/Color.dart b/sky/engine/core/painting/Color.dart
index 65ed9be1db6cabc6fce24b5d471c2dc9def783db..266145ec18e7082d971a4d4dc9c508d2ba135c78 100644
--- a/sky/engine/core/painting/Color.dart
+++ b/sky/engine/core/painting/Color.dart
@@ -5,12 +5,12 @@
 part of dart.sky;
 
 class Color {
-  const Color(this._value);
+  const Color(int value) : _value = (value & 0xFFFFFFFF);
   const Color.fromARGB(int a, int r, int g, int b) :
-    _value = (((a & 0xff) << 24) |
-              ((r & 0xff) << 16) |
-              ((g & 0xff) << 8) |
-              ((b & 0xff) << 0));
+    _value = ((((a & 0xff) << 24) |
+                ((r & 0xff) << 16) |
+                ((g & 0xff) << 8) |
+                ((b & 0xff) << 0)) & 0xFFFFFFFF);
 
   final int _value;
   int get value => _value;