From 24d434d156a91e2ebb5199463ca4b4e85966a11a Mon Sep 17 00:00:00 2001
From: Michael Goderbauer <goderbauer@google.com>
Date: Fri, 8 Jan 2021 12:49:04 -0800
Subject: [PATCH] Revert "Revert "Fix _LateInitializationError for
 RenderObjectElement.renderObject (#70974)" (#73575)" (#73580)

---
 packages/flutter/lib/src/widgets/framework.dart   |  8 ++++----
 packages/flutter/test/widgets/framework_test.dart | 10 ++++++++++
 2 files changed, 14 insertions(+), 4 deletions(-)

diff --git a/packages/flutter/lib/src/widgets/framework.dart b/packages/flutter/lib/src/widgets/framework.dart
index 3978fc3a7fc..71b3bc791e8 100644
--- a/packages/flutter/lib/src/widgets/framework.dart
+++ b/packages/flutter/lib/src/widgets/framework.dart
@@ -5463,8 +5463,8 @@ abstract class RenderObjectElement extends Element {
 
   /// The underlying [RenderObject] for this element.
   @override
-  RenderObject get renderObject => _renderObject;
-  late RenderObject _renderObject;
+  RenderObject get renderObject => _renderObject!;
+  RenderObject? _renderObject;
 
   bool _debugDoingBuild = false;
   @override
@@ -5566,7 +5566,7 @@ abstract class RenderObjectElement extends Element {
 
   void _debugUpdateRenderObjectOwner() {
     assert(() {
-      _renderObject.debugCreator = DebugCreator(this);
+      renderObject.debugCreator = DebugCreator(this);
       return true;
     }());
   }
@@ -6058,7 +6058,7 @@ abstract class RenderObjectElement extends Element {
   @override
   void debugFillProperties(DiagnosticPropertiesBuilder properties) {
     super.debugFillProperties(properties);
-    properties.add(DiagnosticsProperty<RenderObject>('renderObject', renderObject, defaultValue: null));
+    properties.add(DiagnosticsProperty<RenderObject>('renderObject', _renderObject, defaultValue: null));
   }
 }
 
diff --git a/packages/flutter/test/widgets/framework_test.dart b/packages/flutter/test/widgets/framework_test.dart
index 7dc9e7e44ab..9b8e7a12fb7 100644
--- a/packages/flutter/test/widgets/framework_test.dart
+++ b/packages/flutter/test/widgets/framework_test.dart
@@ -1494,6 +1494,12 @@ void main() {
     expect(GestureBinding.instance!.pointerRouter.debugGlobalRouteCount, pointerRouterCount);
     expect(RawKeyboard.instance.keyEventHandler, same(rawKeyEventHandler));
   });
+
+  testWidgets('Can access debugFillProperties without _LateInitializationError', (WidgetTester tester) async {
+    final DiagnosticPropertiesBuilder builder = DiagnosticPropertiesBuilder();
+    TestRenderObjectElement().debugFillProperties(builder);
+    expect(builder.properties.any((DiagnosticsNode property) => property.name == 'renderObject' && property.value == null), isTrue);
+  });
 }
 
 class _FakeFocusManager implements FocusManager {
@@ -1837,3 +1843,7 @@ class FakeLeafRenderObject extends RenderBox {
     size = constraints.biggest;
   }
 }
+
+class TestRenderObjectElement extends RenderObjectElement {
+  TestRenderObjectElement() : super(Table());
+}