fix(auth): Remove request body for deleteTenant (#1461)

This change reverts #1456, which reverted the original PR #1452.

Corresponding internal bug: b/192387245

Author: lisajian

src/auth/auth-api-request.ts

@@ -1887,12 +1887,14 @@ export abstract class AbstractAuthRequestHandler {
    */
   protected invokeRequestHandler(
     urlBuilder: AuthResourceUrlBuilder, apiSettings: ApiSettings,
-    requestData: object, additionalResourceParams?: object): Promise<object> {
+    requestData: object | undefined, additionalResourceParams?: object): Promise<object> {
     return urlBuilder.getUrl(apiSettings.getEndpoint(), additionalResourceParams)
       .then((url) => {
         // Validate request.
-        const requestValidator = apiSettings.getRequestValidator();
-        requestValidator(requestData);
+        if (requestData) {
+          const requestValidator = apiSettings.getRequestValidator();
+          requestValidator(requestData);
+        }
         // Process request.
         const req: HttpRequestConfig = {
           method: apiSettings.getHttpMethod(),
@@ -2120,7 +2122,7 @@ export class AuthRequestHandler extends AbstractAuthRequestHandler {
     if (!validator.isNonEmptyString(tenantId)) {
       return Promise.reject(new FirebaseAuthError(AuthClientErrorCode.INVALID_TENANT_ID));
     }
-    return this.invokeRequestHandler(this.tenantMgmtResourceBuilder, DELETE_TENANT, {}, { tenantId })
+    return this.invokeRequestHandler(this.tenantMgmtResourceBuilder, DELETE_TENANT, undefined, { tenantId })
       .then(() => {
         // Return nothing.
       });

test/unit/auth/auth-api-request.spec.ts

@@ -4547,7 +4547,7 @@ AUTH_REQUEST_HANDLER_TESTS.forEach((handler) => {
           return requestHandler.deleteTenant(tenantId)
             .then((result) => {
               expect(result).to.be.undefined;
-              expect(stub).to.have.been.calledOnce.and.calledWith(callParams(path, method, {}));
+              expect(stub).to.have.been.calledOnce.and.calledWith(callParams(path, method, undefined));
             });
         });
 
@@ -4582,7 +4582,7 @@ AUTH_REQUEST_HANDLER_TESTS.forEach((handler) => {
               throw new Error('Unexpected success');
             }, (error) => {
               expect(error).to.deep.include(expectedError);
-              expect(stub).to.have.been.calledOnce.and.calledWith(callParams(path, method, {}));
+              expect(stub).to.have.been.calledOnce.and.calledWith(callParams(path, method, undefined));
             });
         });
       });