Prepare for dynamically sized views (#138565)

Towards https://github.com/flutter/flutter/issues/134501.

Required to roll https://github.com/flutter/engine/pull/48090 into the framework.

**DO NOT SUBMIT until https://github.com/flutter/flutter/pull/138648 and https://github.com/flutter/engine/pull/48090 are ready.**

packages/flutter/test/rendering/multi_view_binding_test.dart

@@ -188,7 +188,7 @@ class FakeFlutterView extends Fake implements FlutterView  {
   List<Scene> renderedScenes = <Scene>[];
 
   @override
-  void render(Scene scene) {
+  void render(Scene scene, {Size? size}) {
     renderedScenes.add(scene);
   }
 }

packages/flutter_test/lib/src/window.dart

@@ -874,7 +874,8 @@ class TestFlutterView implements FlutterView {
   }
 
   @override
-  void render(Scene scene) {
+  void render(Scene scene, {Size? size}) {
+    // TODO(goderbauer): Wire through size after https://github.com/flutter/engine/pull/48090 rolled in.
     _view.render(scene);
   }
 
@@ -1635,7 +1636,8 @@ class TestWindow implements SingletonFlutterWindow {
     'This feature was deprecated after v3.9.0-0.1.pre.'
   )
   @override
-  void render(Scene scene) {
+  void render(Scene scene, {Size? size}) {
+    // TODO(goderbauer): Wire through size after https://github.com/flutter/engine/pull/48090 rolled in.
     _view.render(scene);
   }
 

packages/flutter_test/test/view_test.dart

@@ -390,7 +390,7 @@ class _FakeFlutterView extends Fake implements FlutterView {
   }
 
   @override
-  void render(Scene scene) {
+  void render(Scene scene, {Size? size}) {
     lastRenderedScene = scene;
   }
 }