Remove unused offset from Layer.addToScene/addChildrenToScene (#91753)

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

@@ -54,8 +54,8 @@ class _ProxyLayer extends Layer {
   final Layer _layer;
 
   @override
-  void addToScene(ui.SceneBuilder builder, [ Offset layerOffset = Offset.zero ]) {
-    _layer.addToScene(builder, layerOffset);
+  void addToScene(ui.SceneBuilder builder) {
+    _layer.addToScene(builder);
   }
 
   @override
@@ -319,8 +319,8 @@ Rect _calculateSubtreeBounds(RenderObject object) {
 /// screenshots render to the scene in the local coordinate system of the layer.
 class _ScreenshotContainerLayer extends OffsetLayer {
   @override
-  void addToScene(ui.SceneBuilder builder, [ Offset layerOffset = Offset.zero ]) {
-    addChildrenToScene(builder, layerOffset);
+  void addToScene(ui.SceneBuilder builder) {
+    addChildrenToScene(builder);
   }
 }
 
@@ -2665,7 +2665,7 @@ class _InspectorOverlayLayer extends Layer {
   double? _textPainterMaxWidth;
 
   @override
-  void addToScene(ui.SceneBuilder builder, [ Offset layerOffset = Offset.zero ]) {
+  void addToScene(ui.SceneBuilder builder) {
     if (!selection.active)
       return;
 
@@ -2694,7 +2694,7 @@ class _InspectorOverlayLayer extends Layer {
       _lastState = state;
       _picture = _buildPicture(state);
     }
-    builder.addPicture(layerOffset, _picture);
+    builder.addPicture(Offset.zero, _picture);
   }
 
   ui.Picture _buildPicture(_InspectorOverlayRenderState state) {

packages/flutter/test/rendering/layer_annotations_test.dart

@@ -845,7 +845,7 @@ class _TestAnnotatedLayer extends Layer {
   final Size? size;
 
   @override
-  EngineLayer? addToScene(SceneBuilder builder, [Offset layerOffset = Offset.zero]) {
+  EngineLayer? addToScene(SceneBuilder builder) {
     return null;
   }
 

packages/flutter/test/rendering/layers_test.dart

@@ -608,7 +608,7 @@ class FakePicture extends Fake implements Picture {
 
 class ConcreteLayer extends Layer {
   @override
-  void addToScene(SceneBuilder builder, [ Offset layerOffset = Offset.zero ]) {}
+  void addToScene(SceneBuilder builder) {}
 }
 
 class _TestAlwaysNeedsAddToSceneLayer extends ContainerLayer {