demo_launcher/lib/main.dart does not have bottom-overscroll

sky/sdk/lib/widgets/fixed_height_scrollable.dart

Index: sky/sdk/lib/widgets/fixed_height_scrollable.dart
diff --git a/sky/sdk/lib/widgets/fixed_height_scrollable.dart b/sky/sdk/lib/widgets/fixed_height_scrollable.dart
index 81cdb20cc9b8c82926eb107271572e3f1eeee935..42d0c7903c8fae75b68deb5ecdd2f54b90ca64a0 100644
--- a/sky/sdk/lib/widgets/fixed_height_scrollable.dart
+++ b/sky/sdk/lib/widgets/fixed_height_scrollable.dart
@@ -23,6 +23,7 @@ abstract class FixedHeightScrollable extends Scrollable {
   /// Subclasses must implement `get itemCount` to tell FixedHeightScrollable
   /// how many items there are in the list.
   int get itemCount;
+  int _previousItemCount;
 
   void syncFields(FixedHeightScrollable source) {
     padding = source.padding;
@@ -39,14 +40,7 @@ abstract class FixedHeightScrollable extends Scrollable {
       _height = newSize.height;
       scrollBehavior.containerHeight = _height;
     });
-  }
-
-  bool scrollTo(double newScrollOffset) {
-    if (_height != null && _height > 0.0) {
-      double maxScrollOffset = math.max(0.0, itemCount * itemHeight - _height);
-      newScrollOffset = math.min(newScrollOffset, maxScrollOffset);
-    }
-    return super.scrollTo(newScrollOffset);
+    _updateScrollOffset();

[eseidel, 2015/07/09 20:40:07]

Unneeded.

   }
 
   void _updateContentsHeight() {
@@ -56,8 +50,17 @@ abstract class FixedHeightScrollable extends Scrollable {
     scrollBehavior.contentsHeight = contentsHeight;
   }
 
+  void _updateScrollOffset() {
+    if (scrollOffset > scrollBehavior.maxScrollOffset)
+      settleScrollOffset();
+  }
+
   Widget buildContent() {
-    _updateContentsHeight();
+    if (itemCount != _previousItemCount) {
+      _previousItemCount = itemCount;
+      _updateContentsHeight();
+      _updateScrollOffset();
+    }
 
     var itemShowIndex = 0;
     var itemShowCount = 0;