add debugFillDescription to OverflowBox

packages/flutter/lib/src/widgets/basic.dart

diff --git a/packages/flutter/lib/src/widgets/basic.dart b/packages/flutter/lib/src/widgets/basic.dart
index 070dbd7..f35fdf2 100644
--- a/packages/flutter/lib/src/widgets/basic.dart
+++ b/packages/flutter/lib/src/widgets/basic.dart
@@ -655,6 +655,18 @@
       ..maxHeight = maxHeight
       ..alignment = alignment;
   }
+
+  void debugFillDescription(List<String> description) {
+    super.debugFillDescription(description);
+    if (minWidth != null)
+      description.add('minWidth: $minWidth');
+    if (maxWidth != null)
+      description.add('maxWidth: $maxWidth');
+    if (minHeight != null)
+      description.add('minHeight: $minHeight');
+    if (maxHeight != null)
+      description.add('maxHeight: $maxHeight');
+  }
 }
 
 class SizedOverflowBox extends OneChildRenderObjectWidget {

packages/flutter/test/widget/overflow_box_test.dart

diff --git a/packages/flutter/test/widget/overflow_box_test.dart b/packages/flutter/test/widget/overflow_box_test.dart
index 7d1cc4f..0fb35cf 100644
--- a/packages/flutter/test/widget/overflow_box_test.dart
+++ b/packages/flutter/test/widget/overflow_box_test.dart
@@ -32,4 +32,20 @@
       expect(box.size, equals(const Size(100.0, 50.0)));
     });
   });
+
+  test('OverflowBox implements debugFillDescription', () {
+    List<String> description = <String>[];
+    new OverflowBox(
+      minWidth: 1.0,
+      maxWidth: 2.0,
+      minHeight: 3.0,
+      maxHeight: 4.0
+    ).debugFillDescription(description);
+    expect(description, [
+      'minWidth: 1.0',
+      'maxWidth: 2.0',
+      'minHeight: 3.0',
+      'maxHeight: 4.0',
+    ]);
+  });
 }