Stop using deprecated analyzer 7.x.y APIs. (#176242)

Preparation for landing
https://dart-review.googlesource.com/c/sdk/+/443460


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responsibilities.
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we expect every widget to implement].
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- [ ] I listed at least one issue that this PR fixes in the description
above.
- [ ] I updated/added relevant documentation (doc comments with `///`).
- [ ] I added new tests to check the change I am making, or this PR is
[test-exempt].
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Fixes] where supported.
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packages/flutter_tools/lib/src/widget_preview/dependency_graph.dart

@@ -11,9 +11,8 @@ import 'package:analyzer/dart/ast/ast.dart';
 import 'package:analyzer/dart/ast/token.dart';
 import 'package:analyzer/dart/ast/visitor.dart';
 import 'package:analyzer/dart/constant/value.dart';
-import 'package:analyzer/dart/element/element2.dart';
+import 'package:analyzer/dart/element/element.dart';
 import 'package:analyzer/diagnostic/diagnostic.dart';
-import 'package:analyzer/error/error.dart';
 import 'package:analyzer/source/line_info.dart';
 
 import '../base/logger.dart';
@@ -34,7 +33,7 @@ typedef PreviewDependencyGraph = Map<PreviewPath, LibraryPreviewNode>;
 /// Visitor which detects previews and extracts [PreviewDetails] for later code
 /// generation.
 class _PreviewVisitor extends RecursiveAstVisitor<void> {
-  _PreviewVisitor({required LibraryElement2 lib})
+  _PreviewVisitor({required LibraryElement lib})
     : packageName = lib.uri.scheme == 'package' ? lib.uri.pathSegments.first : null;
 
   late final String? packageName;
@@ -208,7 +207,7 @@ final class LibraryPreviewNode {
   bool get hasErrors => errors.isNotEmpty;
 
   /// The set of errors found in this library.
-  final errors = <AnalysisError>[];
+  final errors = <Diagnostic>[];
 
   /// Determines the set of errors found in this library.
   ///
@@ -217,8 +216,8 @@ final class LibraryPreviewNode {
     errors.clear();
     for (final String file in files) {
       errors.addAll(
-        ((await context.currentSession.getErrors(file)) as ErrorsResult).errors
-            .where((AnalysisError error) => error.severity == Severity.error)
+        ((await context.currentSession.getErrors(file)) as ErrorsResult).diagnostics
+            .where((error) => error.severity == Severity.error)
             .toList(),
       );
     }

packages/flutter_tools/lib/src/widget_preview/preview_code_generator.dart

@@ -3,8 +3,8 @@
 // found in the LICENSE file.
 
 import 'package:analyzer/dart/constant/value.dart';
-import 'package:analyzer/dart/element/element2.dart' as analyzer;
-import 'package:analyzer/dart/element/element2.dart';
+import 'package:analyzer/dart/element/element.dart' as analyzer;
+import 'package:analyzer/dart/element/element.dart';
 import 'package:analyzer/dart/element/type.dart';
 import 'package:built_collection/built_collection.dart';
 import 'package:code_builder/code_builder.dart' as cb;
@@ -210,7 +210,7 @@ extension on DartObject {
       DartType(isDartCoreInt: true) => cb.literalNum(toIntValue()!),
       DartType(isDartCoreString: true) => cb.literalString(toStringValue()!),
       DartType(isDartCoreNull: true) => cb.literalNull,
-      InterfaceType(element3: EnumElement()) => _createEnumInstance(this),
+      InterfaceType(element: EnumElement()) => _createEnumInstance(this),
       InterfaceType() => _createInstance(type, this),
       FunctionType() => _createTearoff(toFunctionValue()!),
       _ => throw UnsupportedError('Unexpected DartObject type: $runtimeType'),
@@ -242,10 +242,10 @@ extension on DartObject {
     final ConstructorInvocation constructorInvocation = object.constructorInvocation!;
     final ConstructorElement constructor = constructorInvocation.constructor;
     final cb.Expression type = cb.refer(
-      dartType.element3.name3!,
-      _elementToLibraryIdentifier(dartType.element3),
+      dartType.element.name!,
+      _elementToLibraryIdentifier(dartType.element),
     );
-    final String? name = constructor.name3 == 'new' ? null : constructor.name3;
+    final String? name = constructor.name == 'new' ? null : constructor.name;
 
     final List<cb.Expression> positionalArguments = constructorInvocation.positionalArguments
         .map((e) => e.toExpression())

packages/flutter_tools/lib/src/widget_preview/utils.dart

@@ -8,7 +8,7 @@ import 'dart:collection';
 import 'package:analyzer/dart/analysis/results.dart';
 import 'package:analyzer/dart/ast/ast.dart';
 import 'package:analyzer/dart/ast/token.dart';
-import 'package:analyzer/dart/element/element2.dart';
+import 'package:analyzer/dart/element/element.dart';
 import 'package:analyzer/dart/element/type.dart';
 import 'package:analyzer/source/source.dart';
 import 'package:collection/collection.dart';

packages/flutter_tools/test/commands.shard/hermetic/widget_preview/utils/preview_details_matcher.dart

@@ -104,24 +104,24 @@ class PreviewMatcher extends Matcher {
     );
     checkPropertyMatch(
       name: kWrapper,
-      actual: item.getFirstField(kWrapper)?.toFunctionValue2()?.displayName,
+      actual: item.getFirstField(kWrapper)?.toFunctionValue()?.displayName,
       expected: wrapper,
     );
     checkPropertyMatch(
       name: kTheme,
-      actual: item.getFirstField(kTheme)?.toFunctionValue2()?.displayName,
+      actual: item.getFirstField(kTheme)?.toFunctionValue()?.displayName,
       expected: theme,
     );
 
     final DartObject? actualBrightness = item.getFirstField(kBrightness);
     checkPropertyMatch(
       name: kBrightness,
-      actual: (actualBrightness?.isNull ?? true) ? null : actualBrightness!.variable2!.toString(),
+      actual: (actualBrightness?.isNull ?? true) ? null : actualBrightness!.variable!.toString(),
       expected: brightness,
     );
     checkPropertyMatch(
       name: kLocalizations,
-      actual: item.getFirstField(kLocalizations)?.toFunctionValue2()?.displayName,
+      actual: item.getFirstField(kLocalizations)?.toFunctionValue()?.displayName,
       expected: localizations,
     );
     return matches;