Remove io import from devtools_app that was only used for tests (flut…

…ter#6608)

packages/devtools_app/lib/src/shared/memory/adapted_heap_data.dart

@@ -2,8 +2,6 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-import 'dart:io';
-
 import 'package:flutter/foundation.dart';
 import 'package:vm_service/vm_service.dart';
 
@@ -74,17 +72,6 @@ class AdaptedHeapData {
     return AdaptedHeapData(objects);
   }
 
-  @visibleForTesting
-  static Future<AdaptedHeapData> fromFile(
-    String fileName,
-  ) async {
-    final file = File(fileName);
-    final bytes = await file.readAsBytes();
-    final data = bytes.buffer.asByteData();
-    final graph = HeapSnapshotGraph.fromChunks([data]);
-    return AdaptedHeapData.fromHeapSnapshot(graph);
-  }
-
   /// Default value for rootIndex is taken from the doc:
   /// https://github.com/dart-lang/sdk/blob/main/runtime/vm/service/heap_snapshot.md#object-ids
   static const int _defaultRootIndex = 1;

packages/devtools_app/test/test_infra/test_data/memory/heap/heap_data.dart

@@ -2,7 +2,10 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
+import 'dart:io';
+
 import 'package:devtools_app/src/shared/memory/adapted_heap_data.dart';
+import 'package:vm_service/vm_service.dart';
 
 const _dataDir = 'test/test_infra/test_data/memory/heap/';
 
@@ -20,8 +23,7 @@ class GoldenHeapTest {
   /// Loads the heap data from a file.
   ///
   /// Format is format used by [NativeRuntime.writeHeapSnapshotToFile].
-  Future<AdaptedHeapData> loadHeap() =>
-      AdaptedHeapData.fromFile('$_dataDir$fileName');
+  Future<AdaptedHeapData> loadHeap() => heapFromFile('$_dataDir$fileName');
 }
 
 List<GoldenHeapTest> goldenHeapTests = <GoldenHeapTest>[
@@ -42,3 +44,13 @@ List<GoldenHeapTest> goldenHeapTests = <GoldenHeapTest>[
     appClassName: 'MyApp',
   ),
 ];
+
+Future<AdaptedHeapData> heapFromFile(
+  String fileName,
+) async {
+  final file = File(fileName);
+  final bytes = await file.readAsBytes();
+  final data = bytes.buffer.asByteData();
+  final graph = HeapSnapshotGraph.fromChunks([data]);
+  return AdaptedHeapData.fromHeapSnapshot(graph);
+}