Fix formatting from fixes to dart format

Author: jamesderlin

packages/visibility_detector/example/lib/main.dart

@@ -296,7 +296,7 @@ class DemoPageCell extends StatelessWidget {
     required this.primaryIndex,
     required this.secondaryIndex,
     required this.useSlivers,
-  })   : _cellName = 'Item $primaryIndex-$secondaryIndex',
+  })  : _cellName = 'Item $primaryIndex-$secondaryIndex',
         _backgroundColor = ((primaryIndex + secondaryIndex) % 2 == 0)
             ? Colors.pink[200]
             : Colors.yellow[200],

packages/visibility_detector/lib/src/render_sliver_visibility_detector.dart

@@ -22,7 +22,7 @@ class RenderSliverVisibilityDetector extends RenderProxySliver {
     RenderSliver? sliver,
     required this.key,
     required VisibilityChangedCallback? onVisibilityChanged,
-  })   : _onVisibilityChanged = onVisibilityChanged,
+  })  : _onVisibilityChanged = onVisibilityChanged,
         super(sliver);
 
   /// The key for the corresponding [VisibilityDetector] widget.

packages/visibility_detector/lib/src/render_visibility_detector.dart

@@ -20,7 +20,7 @@ class RenderVisibilityDetector extends RenderProxyBox {
     RenderBox? child,
     required this.key,
     required VisibilityChangedCallback? onVisibilityChanged,
-  })   : assert(key != null),
+  })  : assert(key != null),
         _onVisibilityChanged = onVisibilityChanged,
         super(child);
 

packages/visibility_detector/lib/src/visibility_detector.dart

@@ -33,7 +33,7 @@ class VisibilityDetector extends SingleChildRenderObjectWidget {
     required Key key,
     required Widget child,
     required this.onVisibilityChanged,
-  })   : assert(key != null),
+  })  : assert(key != null),
         assert(child != null),
         super(key: key, child: child);
 
@@ -70,7 +70,7 @@ class SliverVisibilityDetector extends SingleChildRenderObjectWidget {
     required Key key,
     required Widget sliver,
     required this.onVisibilityChanged,
-  })   : assert(key != null),
+  })  : assert(key != null),
         assert(sliver != null),
         super(key: key, child: sliver);