Use static strings from FunctionElement where possible

This improves discovery, refactoring, etc.

I did not change any locations which would have required interpolation,
or tests which refer to a String immediately nearby (in tests).

Change-Id: I8479fd7822713e878e56fdf5ec35969492049333
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/213580
Reviewed-by: Brian Wilkerson <brianwilkerson@google.com>
Commit-Queue: Samuel Rawlins <srawlins@google.com>

pkg/analysis_server/lib/src/services/completion/dart/feature_computer.dart

@@ -21,10 +21,11 @@ import 'package:analyzer/dart/element/element.dart'
         Element,
         ElementKind,
         FieldElement,
+        FunctionElement,
         LibraryElement,
+        LocalVariableElement,
         PropertyAccessorElement,
-        TopLevelVariableElement,
-        LocalVariableElement;
+        TopLevelVariableElement;
 import 'package:analyzer/dart/element/type.dart';
 import 'package:analyzer/dart/element/type_provider.dart';
 import 'package:analyzer/dart/element/type_system.dart';
@@ -322,7 +323,9 @@ class FeatureComputer {
       // override of `noSuchMethod`.
       return 0.0;
     }
-    return proposedMemberName == 'noSuchMethod' ? -1.0 : 0.0;
+    return proposedMemberName == FunctionElement.NO_SUCH_METHOD_METHOD_NAME
+        ? -1.0
+        : 0.0;
   }
 
   /// Return the value of the _keyword_ feature for the [keyword] when

pkg/analysis_server/lib/src/services/completion/dart/suggestion_builder.dart

@@ -457,9 +457,8 @@ class SuggestionBuilder {
 
   /// Add a suggestion for the `call` method defined on functions.
   void suggestFunctionCall() {
-    const callString = 'call';
-    final element = protocol.Element(
-        protocol.ElementKind.METHOD, callString, protocol.Element.makeFlags(),
+    final element = protocol.Element(protocol.ElementKind.METHOD,
+        FunctionElement.CALL_METHOD_NAME, protocol.Element.makeFlags(),
         location: null,
         typeParameters: null,
         parameters: '()',
@@ -467,8 +466,8 @@ class SuggestionBuilder {
     _add(CompletionSuggestion(
       CompletionSuggestionKind.INVOCATION,
       Relevance.callFunction,
-      callString,
-      callString.length,
+      FunctionElement.CALL_METHOD_NAME,
+      FunctionElement.CALL_METHOD_NAME.length,
       0,
       false,
       false,

pkg/analyzer/lib/src/dart/analysis/index.dart

@@ -140,7 +140,8 @@ class IndexElementInfo {
       if (elementKind == ElementKind.CONSTRUCTOR) {
         kind = IndexSyntheticElementKind.constructor;
         element = element.enclosingElement!;
-      } else if (element is FunctionElement && element.name == 'loadLibrary') {
+      } else if (element is FunctionElement &&
+          element.name == FunctionElement.LOAD_LIBRARY_NAME) {
         kind = IndexSyntheticElementKind.loadLibrary;
         element = element.library;
       } else if (elementKind == ElementKind.FIELD) {

pkg/analyzer/lib/src/dart/element/inheritance_manager3.dart

@@ -43,7 +43,8 @@ class GetterMethodConflict extends Conflict {
 
 /// Manages knowledge about interface types and their members.
 class InheritanceManager3 {
-  static final _noSuchMethodName = Name(null, 'noSuchMethod');
+  static final _noSuchMethodName =
+      Name(null, FunctionElement.NO_SUCH_METHOD_METHOD_NAME);
 
   /// Cached instance interfaces for [ClassElement].
   final Map<ClassElement, Interface> _interfaces = {};

pkg/analyzer/lib/src/dart/element/type_system.dart

@@ -316,7 +316,9 @@ class TypeSystemImpl implements TypeSystem {
   /// return the function type for the call method, otherwise return null.
   FunctionType? getCallMethodType(DartType t) {
     if (t is InterfaceType) {
-      return t.lookUpMethod2('call', t.element.library)?.type;
+      return t
+          .lookUpMethod2(FunctionElement.CALL_METHOD_NAME, t.element.library)
+          ?.type;
     }
     return null;
   }

pkg/analyzer/lib/src/dart/resolver/property_element_resolver.dart

@@ -350,7 +350,8 @@ class PropertyElementResolver {
 
     var targetType = target.typeOrThrow;
 
-    if (targetType is FunctionType && propertyName.name == 'call') {
+    if (targetType is FunctionType &&
+        propertyName.name == FunctionElement.CALL_METHOD_NAME) {
       return PropertyElementResolverResult(
         functionTypeCallType: targetType,
       );

pkg/analyzer/lib/src/dart/resolver/type_property_resolver.dart

@@ -170,14 +170,16 @@ class TypePropertyResolver {
         if (_hasGetterOrSetter) {
           return _toResult();
         }
-        if (receiverTypeResolved.isDartCoreFunction && _name == 'call') {
+        if (receiverTypeResolved.isDartCoreFunction &&
+            _name == FunctionElement.CALL_METHOD_NAME) {
           _needsGetterError = false;
           _needsSetterError = false;
           return _toResult();
         }
       }
 
-      if (receiverTypeResolved is FunctionType && _name == 'call') {
+      if (receiverTypeResolved is FunctionType &&
+          _name == FunctionElement.CALL_METHOD_NAME) {
         return _toResult();
       }
 

pkg/analyzer/lib/src/error/duplicate_definition_verifier.dart

@@ -14,7 +14,7 @@ class DuplicateDefinitionVerifier {
   static final Set<String> _enumInstanceMembers = {
     'hashCode',
     'index',
-    'noSuchMethod',
+    FunctionElement.NO_SUCH_METHOD_METHOD_NAME,
     'runtimeType',
     'toString',
   };

pkg/analyzer/lib/src/generated/error_verifier.dart

@@ -2396,7 +2396,7 @@ class ErrorVerifier extends RecursiveAstVisitor<void>
         name == 'hashCode' ||
         name == 'toString' ||
         name == 'runtimeType' ||
-        name == 'noSuchMethod') {
+        name == FunctionElement.NO_SUCH_METHOD_METHOD_NAME) {
       errorReporter.reportErrorForNode(
         CompileTimeErrorCode.EXTENSION_DECLARES_MEMBER_OF_OBJECT,
         node.name,