Convert WebappActivityTestBase and direct children to JUnit4.

chrome/android/javatests/src/org/chromium/chrome/browser/hardware_acceleration/WebappActivityHWATest.java

 // Copyright 2015 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.hardware_acceleration;
 
 import android.support.test.filters.SmallTest;
 
+import org.junit.Before;
+import org.junit.Rule;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+
+import org.chromium.base.test.util.CommandLineFlags;
+import org.chromium.chrome.browser.ChromeSwitches;
 import org.chromium.chrome.browser.webapps.WebappActivity;
-import org.chromium.chrome.browser.webapps.WebappActivityTestBase;
+import org.chromium.chrome.browser.webapps.WebappActivityTestRule;
+import org.chromium.chrome.test.ChromeActivityTestRule;
+import org.chromium.chrome.test.ChromeJUnit4ClassRunner;
 
 /**
  * Tests that WebappActivity is hardware accelerated only high-end devices.
  */
-public class WebappActivityHWATest extends WebappActivityTestBase {
-    @Override
-    protected void setUp() throws Exception {
-        super.setUp();
-        startWebappActivity();
+@RunWith(ChromeJUnit4ClassRunner.class)
+@CommandLineFlags.Add({ChromeSwitches.DISABLE_FIRST_RUN_EXPERIENCE,
+        ChromeActivityTestRule.DISABLE_NETWORK_PREDICTION_FLAG})
+public class WebappActivityHWATest {
+    @Rule
+    public final WebappActivityTestRule mActivityTestRule = new WebappActivityTestRule();
+
+    @Before
+    public void setUp() throws Exception {
+        mActivityTestRule.startWebappActivity();
     }
 
+    @Test
     @SmallTest
     public void testHardwareAcceleration() throws Exception {
-        WebappActivity activity = getActivity();
+        WebappActivity activity = mActivityTestRule.getActivity();
         Utils.assertHardwareAcceleration(activity);
     }
 }