From 5bfb2200b0e5a7981900a2811e7586c0f7773145 Mon Sep 17 00:00:00 2001
From: gaaclarke <30870216+gaaclarke@users.noreply.github.com>
Date: Tue, 24 Oct 2023 14:08:45 -0700
Subject: [PATCH] Migrated away from UnmodifiableUint8ListView
 (flutter/engine#47276)

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---
 engine/src/flutter/lib/ui/fixtures/ui_test.dart     | 13 ++++++++++---
 engine/src/flutter/lib/ui/platform_dispatcher.dart  |  2 +-
 .../fuchsia/dart-pkg/zircon/test/zircon_tests.dart  |  4 ++--
 3 files changed, 13 insertions(+), 6 deletions(-)

diff --git a/engine/src/flutter/lib/ui/fixtures/ui_test.dart b/engine/src/flutter/lib/ui/fixtures/ui_test.dart
index dc4f75bb67f..7a79cda95ca 100644
--- a/engine/src/flutter/lib/ui/fixtures/ui_test.dart
+++ b/engine/src/flutter/lib/ui/fixtures/ui_test.dart
@@ -273,9 +273,16 @@ void platformMessagePortResponseTest() async {
 @pragma('vm:entry-point')
 void platformMessageResponseTest() {
   _callPlatformMessageResponseDart((ByteData? result) {
-    if (result is UnmodifiableByteDataView &&
-        result.lengthInBytes == 100) {
-      _finishCallResponse(true);
+    if (result is ByteData && result.lengthInBytes == 100) {
+      int value = result.getInt8(0);
+      bool didThrowOnModify = false;
+      try {
+        result.setInt8(0, value);
+      } catch (e) {
+        didThrowOnModify = true;
+      }
+      // This should be a read only buffer.
+      _finishCallResponse(didThrowOnModify);
     } else {
       _finishCallResponse(false);
     }
diff --git a/engine/src/flutter/lib/ui/platform_dispatcher.dart b/engine/src/flutter/lib/ui/platform_dispatcher.dart
index 66e68b88be5..aac78856563 100644
--- a/engine/src/flutter/lib/ui/platform_dispatcher.dart
+++ b/engine/src/flutter/lib/ui/platform_dispatcher.dart
@@ -73,7 +73,7 @@ const String _kFlutterKeyDataChannel = 'flutter/keydata';
 
 @pragma('vm:entry-point')
 ByteData? _wrapUnmodifiableByteData(ByteData? byteData) =>
-    byteData == null ? null : UnmodifiableByteDataView(byteData);
+    byteData?.asUnmodifiableView();
 
 /// A token that represents a root isolate.
 class RootIsolateToken {
diff --git a/engine/src/flutter/shell/platform/fuchsia/dart-pkg/zircon/test/zircon_tests.dart b/engine/src/flutter/shell/platform/fuchsia/dart-pkg/zircon/test/zircon_tests.dart
index a3760a20ccb..a0e380fb34d 100644
--- a/engine/src/flutter/shell/platform/fuchsia/dart-pkg/zircon/test/zircon_tests.dart
+++ b/engine/src/flutter/shell/platform/fuchsia/dart-pkg/zircon/test/zircon_tests.dart
@@ -589,7 +589,7 @@ void main() {
       expect(fileResult.status, equals(ZX.OK));
       MapResult mapResult = System.vmoMap(fileResult.handle);
       expect(mapResult.status, equals(ZX.OK));
-      Uint8List fileData = UnmodifiableUint8ListView(mapResult.data);
+      Uint8List fileData = mapResult.data.asUnmodifiableView();
       String fileString = utf8.decode(fileData.sublist(0, fileResult.numBytes));
       expect(fileString, equals(fuchsia));
     });
@@ -610,7 +610,7 @@ void main() {
       // Read from the duplicate.
       MapResult mapResult = System.vmoMap(duplicate);
       expect(mapResult.status, equals(ZX.OK));
-      Uint8List vmoData = UnmodifiableUint8ListView(mapResult.data);
+      Uint8List vmoData = mapResult.data.asUnmodifiableView();
       String vmoString = utf8.decode(vmoData.sublist(0, data.length));
       expect(vmoString, equals(fuchsia));
     });