Change AccountManagerHelper initialization

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

Index: chrome/android/javatests/src/org/chromium/chrome/browser/signin/OAuth2TokenServiceTest.java
diff --git a/chrome/android/javatests/src/org/chromium/chrome/browser/signin/OAuth2TokenServiceTest.java b/chrome/android/javatests/src/org/chromium/chrome/browser/signin/OAuth2TokenServiceTest.java
index 8db3cd48c2e06bd26a7673997cc1dcbd87b96b08..90dd7044caccec2628f6de82126435290d2dc73f 100644
--- a/chrome/android/javatests/src/org/chromium/chrome/browser/signin/OAuth2TokenServiceTest.java
+++ b/chrome/android/javatests/src/org/chromium/chrome/browser/signin/OAuth2TokenServiceTest.java
@@ -8,7 +8,6 @@ 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;
@@ -35,13 +34,8 @@ public class OAuth2TokenServiceTest {
     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);
     }
 
     /*