Make nodeCovering a method on CompilationUnitImpl rather than an extension method

This allows us to traverse the children without needing to create lists.
It also allows us to iterate over lists of nodes more efficiently.

Tested against the script that computes fixes for 10,000 diagnostics,
I'm seeing the following result.

  Before this CL the average time was 10692.4 ms.
  After this CL the average time was 1900.0 ms.

That's just over an 82% improvement.

Change-Id: Ideff745288c8990e9948b22c5204d176af3cac6e
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/426904
Reviewed-by: Konstantin Shcheglov <[email protected]>
Commit-Queue: Brian Wilkerson <[email protected]>

Author: bwilkerson

pkg/analysis_server/lib/src/analysis_server.dart

@@ -78,7 +78,6 @@ import 'package:analyzer/src/generated/sdk.dart';
 import 'package:analyzer/src/util/file_paths.dart' as file_paths;
 import 'package:analyzer/src/util/performance/operation_performance.dart';
 import 'package:analyzer/src/utilities/extensions/analysis_session.dart';
-import 'package:analyzer/utilities/extensions/ast.dart';
 import 'package:analyzer_plugin/protocol/protocol.dart';
 import 'package:analyzer_plugin/src/protocol/protocol_internal.dart'
     as analyzer_plugin;

pkg/analysis_server/lib/src/cider/rename.dart

@@ -18,7 +18,6 @@ import 'package:analyzer/src/generated/java_core.dart';
 import 'package:analyzer/src/utilities/extensions/collection.dart';
 import 'package:analyzer/src/utilities/extensions/element.dart';
 import 'package:analyzer/src/utilities/extensions/flutter.dart';
-import 'package:analyzer/utilities/extensions/ast.dart';
 
 class CanRenameResponse {
   final LineInfo lineInfo;

pkg/analysis_server/lib/src/computer/computer_call_hierarchy.dart

@@ -11,7 +11,6 @@ import 'package:analyzer/dart/element/element.dart';
 import 'package:analyzer/source/source_range.dart';
 import 'package:analyzer/src/dart/ast/element_locator.dart';
 import 'package:analyzer/src/dart/element/element.dart';
-import 'package:analyzer/utilities/extensions/ast.dart';
 
 /// Returns the container for [element] that should be used in Call Hierarchy.
 ///

pkg/analysis_server/lib/src/computer/computer_hover.dart

@@ -11,7 +11,6 @@ import 'package:analyzer/dart/element/element.dart';
 import 'package:analyzer/dart/element/type.dart';
 import 'package:analyzer/src/dart/ast/element_locator.dart';
 import 'package:analyzer/src/dartdoc/dartdoc_directive_info.dart';
-import 'package:analyzer/utilities/extensions/ast.dart';
 import 'package:path/path.dart' as path;
 
 /// Information about a library to display in a hover.

pkg/analysis_server/lib/src/computer/computer_lazy_type_hierarchy.dart

@@ -13,7 +13,6 @@ import 'package:analyzer/dart/element/element.dart';
 import 'package:analyzer/dart/element/type.dart';
 import 'package:analyzer/source/source_range.dart';
 import 'package:analyzer/src/dart/element/element.dart';
-import 'package:analyzer/utilities/extensions/ast.dart';
 
 /// A lazy computer for Type Hierarchies.
 ///

pkg/analysis_server/lib/src/computer/computer_selection_ranges.dart

@@ -3,7 +3,6 @@
 // BSD-style license that can be found in the LICENSE file.
 
 import 'package:analyzer/dart/ast/ast.dart';
-import 'package:analyzer/utilities/extensions/ast.dart';
 
 /// Computes selection ranges for a specific offset of a Dart [CompilationUnit].
 ///

pkg/analysis_server/lib/src/computer/computer_signature.dart

@@ -10,7 +10,6 @@ import 'package:analyzer/dart/element/element.dart';
 import 'package:analyzer/dart/element/type.dart';
 import 'package:analyzer/src/dart/ast/element_locator.dart';
 import 'package:analyzer/src/dartdoc/dartdoc_directive_info.dart';
-import 'package:analyzer/utilities/extensions/ast.dart';
 
 /// A computer for the signature at the specified offset of a Dart
 /// [CompilationUnit].

pkg/analysis_server/lib/src/computer/computer_type_arguments_signature.dart

@@ -10,7 +10,6 @@ import 'package:analyzer/dart/ast/ast.dart';
 import 'package:analyzer/dart/element/element.dart';
 import 'package:analyzer/src/dart/ast/element_locator.dart';
 import 'package:analyzer/src/dartdoc/dartdoc_directive_info.dart';
-import 'package:analyzer/utilities/extensions/ast.dart';
 
 /// A computer for the signature help information about the type parameters for
 /// the [TypeArgumentList] surrounding the specified offset of a Dart

pkg/analysis_server/lib/src/handler/legacy/edit_get_available_refactorings.dart

@@ -9,7 +9,6 @@ import 'package:analysis_server/src/handler/legacy/legacy_handler.dart';
 import 'package:analysis_server/src/services/refactoring/legacy/refactoring.dart';
 import 'package:analysis_server/src/utilities/extensions/ast.dart';
 import 'package:analyzer/dart/element/element.dart';
-import 'package:analyzer/utilities/extensions/ast.dart';
 import 'package:analyzer_plugin/protocol/protocol_common.dart';
 
 /// The handler for the `edit.getAvailableRefactorings` request.

pkg/analysis_server/lib/src/lsp/handlers/code_actions/dart.dart

@@ -29,7 +29,6 @@ import 'package:analyzer/dart/analysis/session.dart'
     show InconsistentAnalysisException;
 import 'package:analyzer/dart/element/element.dart';
 import 'package:analyzer/src/util/performance/operation_performance.dart';
-import 'package:analyzer/utilities/extensions/ast.dart';
 
 /// Produces [CodeActionLiteral]s from Dart source commands, fixes, assists and
 /// refactors from the server.