Add operator==, hashCode, and toString for Rect and Point dart classes.

sky/engine/core/painting/Rect.dart

Index: sky/engine/core/painting/Rect.dart
diff --git a/sky/engine/core/painting/Rect.dart b/sky/engine/core/painting/Rect.dart
index cb2afec7d773e004e1ec77a276ea82dce7d6df77..64b086ada90d568e3b708fffeecefe1b9ec805f2 100644
--- a/sky/engine/core/painting/Rect.dart
+++ b/sky/engine/core/painting/Rect.dart
@@ -14,4 +14,19 @@ class Rect {
   void setLTRB(double left, double top, double right, double bottom) {

[sethladd, 2015/05/27 22:19:49]

Dart has named constructors. You could do:

Rect.LTRB(double left, double top, double right, double bottom) {
  _value = new Float32List.fromList([left, top, right, bottom]);
}

[Matt Perry, 2015/05/28 17:05:54]

Done.

     _value = new Float32List.fromList([left, top, right, bottom]);
   }
+
+  bool operator ==(other) {
+    if (!(other is Rect)) return false;
+    for (var i = 0; i < 4; ++i) {
+      if (_value[i] != other._value[i])
+        return false;
+    }
+    return true;
+  }
+  int get hashCode {
+    return _value.fold(373, (value, item) => (37 * value + item.hashCode));
+  }
+  String toString() {

[sethladd, 2015/05/27 22:19:49]

consider using => here

[Matt Perry, 2015/05/28 17:05:54]

Done.

+    return "Rect.LTRB($left, $top, $right, $bottom)";
+  }
 }