message: remove unused typeChecker
diff: @@ -17,7 +17,6 @@ function GetPossibleDescriptor(node: ts.Node): ts.Expression {
  }
  export class MockDefiner {
  - private _typeChecker: ts.TypeChecker;
  private _neededImportIdentifierPerFile: { [key: string]: ts.Identifier } = {};
  private _factoryRegistrationsPerFile: { [key: string]: Array<{ key: ts.Declaration; factory: ts.Expression }> } = {};
  private _factoryCache: FactoryDefinitionCache;
  @@ -33,7 +32,6 @@ export class MockDefiner {
  private constructor() {
  this._factoryCache = new FactoryDefinitionCache();
  - this._typeChecker = TypeChecker();
  }
  public setFileNameFromNode(node: ts.TypeNode): void {
  @@ -50,8 +48,8 @@ export class MockDefiner {
  }
  public getMockFactory(node: PossibleTypeNode): ts.Expression {
  - this._typeChecker = TypeChecker();
  - const definedType: ts.Type = this._typeChecker.getTypeAtLocation(node);
  + const typeChecker = TypeChecker();
  + const definedType: ts.Type = typeChecker.getTypeAtLocation(node);
  let declaration = TypescriptHelper.GetDeclarationFromType(definedType);
  const thisFileName: string = this._fileName;
  