Change AccountManagerHelper initialization

chrome/android/javatests/src/org/chromium/chrome/browser/signin/OAuth2TokenServiceTest.java

 // Copyright 2013 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.signin;
 
 import android.accounts.Account;
 import android.support.test.InstrumentationRegistry;
 import android.support.test.filters.SmallTest;
 
-import org.junit.After;
 import org.junit.Assert;
 import org.junit.Before;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 
 import org.chromium.base.test.util.AdvancedMockContext;
 import org.chromium.base.test.util.DisabledTest;
 import org.chromium.base.test.util.Feature;
 import org.chromium.chrome.test.ChromeJUnit4ClassRunner;
 import org.chromium.components.signin.AccountManagerHelper;
 import org.chromium.components.signin.test.util.AccountHolder;
 import org.chromium.components.signin.test.util.FakeAccountManagerDelegate;
 
 import java.util.Arrays;
 import java.util.concurrent.TimeUnit;
 
 /** Tests for OAuth2TokenService. */
 @RunWith(ChromeJUnit4ClassRunner.class)
 public class OAuth2TokenServiceTest {
     private AdvancedMockContext mContext;
     private FakeAccountManagerDelegate mAccountManager;
 
     @Before
     public void setUp() throws Exception {
         mContext = new AdvancedMockContext(
                 InstrumentationRegistry.getInstrumentation().getTargetContext());
-        mAccountManager = new FakeAccountManagerDelegate(mContext);
-        AccountManagerHelper.overrideAccountManagerHelperForTests(mContext, mAccountManager);
-    }
-
-    @After
-    public void tearDown() {
-        AccountManagerHelper.resetAccountManagerHelperForTests();
+        mAccountManager = new FakeAccountManagerDelegate();
+        AccountManagerHelper.overrideAccountManagerHelperForTests(mAccountManager);
     }
 
     /*
      *  @SmallTest
      *  @Feature({"Sync"})
      */
     @Test
     @DisabledTest(message = "crbug.com/533417")
     public void testGetAccountsNoAccountsRegistered() {
         String[] accounts = OAuth2TokenService.getAccounts();
@@ skipping 70 matching lines @@
                                               .hasBeenAccepted(oauth2Scope, true)
                                               .authToken(oauth2Scope, expectedToken)
                                               .build();
         mAccountManager.addAccountHolderExplicitly(accountHolder);
 
         String accessToken = OAuth2TokenService.getOAuth2AccessTokenWithTimeout(
                 mContext, account, scope, 5, TimeUnit.SECONDS);
         Assert.assertEquals(expectedToken, accessToken);
     }
 }