[Codegen 110] Add a nullLiteralTypeAnnotation: string property into the Parser object

packages/react-native-codegen/src/parsers/flow/components/events.js

@@ -223,7 +223,7 @@ function findEventArgumentsAndType(
         : null;
     if (
       typeAnnotation.typeParameters.params[0].type ===
-      'NullLiteralTypeAnnotation'
+      parser.nullLiteralTypeAnnotation
     ) {
       return {
         argumentProps: [],

packages/react-native-codegen/src/parsers/flow/parser.js

@@ -51,6 +51,8 @@ const {
 class FlowParser implements Parser {
   typeParameterInstantiation: string = 'TypeParameterInstantiation';
 
+  nullLiteralTypeAnnotation: string = 'NullLiteralTypeAnnotation';
+
   isProperty(property: $FlowFixMe): boolean {
     return property.type === 'ObjectTypeProperty';
   }

packages/react-native-codegen/src/parsers/parser.js

@@ -72,6 +72,11 @@ export interface Parser {
    */
   typeParameterInstantiation: string;
 
+  /**
+   * This is the NullLiteralTypeAnnotation value
+   */
+  nullLiteralTypeAnnotation: string;
+
   /**
    * Given a declaration, it returns true if it is a property
    */

packages/react-native-codegen/src/parsers/parserMock.js

@@ -50,6 +50,8 @@ const schemaMock = {
 export class MockedParser implements Parser {
   typeParameterInstantiation: string = 'TypeParameterInstantiation';
 
+  nullLiteralTypeAnnotation: string = 'NullLiteralTypeAnnotation';
+
   isProperty(property: $FlowFixMe): boolean {
     return property.type === 'ObjectTypeProperty';
   }

packages/react-native-codegen/src/parsers/typescript/components/events.js

@@ -237,7 +237,7 @@ function findEventArgumentsAndType(
         : null;
 
     switch (typeAnnotation.typeParameters.params[0].type) {
-      case 'TSNullKeyword':
+      case parser.nullLiteralTypeAnnotation:
       case 'TSUndefinedKeyword':
         return {
           argumentProps: [],

packages/react-native-codegen/src/parsers/typescript/parser.js

@@ -50,6 +50,8 @@ const {
 class TypeScriptParser implements Parser {
   typeParameterInstantiation: string = 'TSTypeParameterInstantiation';
 
+  nullLiteralTypeAnnotation: string = 'TSNullKeyword';
+
   isProperty(property: $FlowFixMe): boolean {
     return property.type === 'TSPropertySignature';
   }