Extend Sky's RenderFlex with intrinsic sizes and compute cross-size height

sky/examples/lib/solid_color_box.dart

Index: sky/examples/lib/solid_color_box.dart
diff --git a/sky/examples/lib/solid_color_box.dart b/sky/examples/lib/solid_color_box.dart
index 9c650ce39671740aca14981eaf22de68f5bfb9ee..0a9bd38ac2f3ff6fe4f960adaa8d2bc9fe71ad75 100644
--- a/sky/examples/lib/solid_color_box.dart
+++ b/sky/examples/lib/solid_color_box.dart
@@ -14,19 +14,19 @@ class RenderSolidColorBox extends RenderDecoratedBox {
         super(decoration: new BoxDecoration(backgroundColor: backgroundColor));
 
   double getMinIntrinsicWidth(BoxConstraints constraints) {
-    return constraints.constrainWidth(desiredSize.width);
+    return constraints.constrainWidth(0.0);
   }
 
   double getMaxIntrinsicWidth(BoxConstraints constraints) {
-    return constraints.constrainWidth(desiredSize.width);
+    return constraints.constrainWidth(0.0);

[abarth-chromium, 2015/06/10 02:05:53]

Why this change?

[jackson, 2015/06/10 04:33:39]

It seemed like most users of RenderSolidColorBox were setting desiredSize to
Size.infinite, but clearly they didn't need infinite space to display their
contents. Probably what we should do is special case infinity and use zero
instead. I can do that.

   }
 
   double getMinIntrinsicHeight(BoxConstraints constraints) {
-    return constraints.constrainHeight(desiredSize.height);
+    return constraints.constrainHeight(0.0);
   }
 
   double getMaxIntrinsicHeight(BoxConstraints constraints) {
-    return constraints.constrainHeight(desiredSize.height);
+    return constraints.constrainHeight(0.0);
   }
 
   void performLayout() {