WIP: fixes from @schmidt-sebastian's review

Author: jshcrowthe

src/database/api/Database.ts

@@ -6,8 +6,7 @@ import { Reference } from './Reference';
 import { Repo } from '../core/Repo';
 import { RepoManager } from '../core/RepoManager';
 import { validateArgCount } from '../../utils/validation';
-import { FirebaseApp } from "../../app/firebase_app";
-zimport { validateUrl } from '../core/util/validation';
+import { validateUrl } from '../core/util/validation';
 import { FirebaseApp, FirebaseService } from '../../app/firebase_app';
 import { RepoInfo } from '../core/RepoInfo';
 
@@ -109,13 +108,8 @@ export class Database implements FirebaseService {
   }
 }
 
-Object.defineProperty(Repo.prototype, 'database', {
-  get(): Database {
-    return this.__database || (this.__database = new Database(this));
-  }
-});
-
-export class DatabaseInternals {
+class DatabaseInternals {
+  database
   /** @param {!Database} database */
   constructor(public database: Database) {
   }