Revert of [Reland] Refactor WebappRegistry into a singleton instance.

chrome/android/javatests/src/org/chromium/chrome/browser/webapps/TestFetchStorageCallback.java

Index: chrome/android/javatests/src/org/chromium/chrome/browser/webapps/TestFetchStorageCallback.java
diff --git a/chrome/android/javatests/src/org/chromium/chrome/browser/webapps/TestFetchStorageCallback.java b/chrome/android/javatests/src/org/chromium/chrome/browser/webapps/TestFetchStorageCallback.java
deleted file mode 100644
index 567fb537f47e6662bae7dc8176e0e97d588f716f..0000000000000000000000000000000000000000
--- a/chrome/android/javatests/src/org/chromium/chrome/browser/webapps/TestFetchStorageCallback.java
+++ /dev/null
@@ -1,25 +0,0 @@
-// Copyright 2016 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-package org.chromium.chrome.browser.webapps;
-
-import org.chromium.content.browser.test.util.CallbackHelper;
-
-/**
- * CallbackHelper subclass which implements WebappRegistry.FetchWebappDataStorageCallback for tests.
- */
-public class TestFetchStorageCallback
-        extends CallbackHelper implements WebappRegistry.FetchWebappDataStorageCallback {
-    protected WebappDataStorage mStorage;
-
-    @Override
-    public void onWebappDataStorageRetrieved(WebappDataStorage storage) {
-        mStorage = storage;
-        notifyCalled();
-    }
-
-    public WebappDataStorage getStorage() {
-        return mStorage;
-    }
-}