Reland: Convert ChromeActivityTestCaseBase direct children to JUnit4

chrome/android/javatests/src/org/chromium/chrome/browser/metrics/PageLoadMetricsTest.java

Index: chrome/android/javatests/src/org/chromium/chrome/browser/metrics/PageLoadMetricsTest.java
diff --git a/chrome/android/javatests/src/org/chromium/chrome/browser/metrics/PageLoadMetricsTest.java b/chrome/android/javatests/src/org/chromium/chrome/browser/metrics/PageLoadMetricsTest.java
index c8ff4deca617a713f4274e370855d26747243caf..d718c7f0f04f42fa910f77f41e8688f2dfc9adbc 100644
--- a/chrome/android/javatests/src/org/chromium/chrome/browser/metrics/PageLoadMetricsTest.java
+++ b/chrome/android/javatests/src/org/chromium/chrome/browser/metrics/PageLoadMetricsTest.java
@@ -4,13 +4,24 @@
 
 package org.chromium.chrome.browser.metrics;
 
+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.Rule;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+
 import org.chromium.base.ThreadUtils;
+import org.chromium.base.test.util.CommandLineFlags;
 import org.chromium.base.test.util.RetryOnFailure;
 import org.chromium.chrome.browser.ChromeActivity;
+import org.chromium.chrome.browser.ChromeSwitches;
 import org.chromium.chrome.browser.tab.Tab;
-import org.chromium.chrome.test.ChromeActivityTestCaseBase;
+import org.chromium.chrome.test.ChromeActivityTestRule;
+import org.chromium.chrome.test.ChromeJUnit4ClassRunner;
 import org.chromium.content_public.browser.WebContents;
 import org.chromium.net.test.EmbeddedTestServer;
 
@@ -20,11 +31,14 @@ import java.util.concurrent.TimeUnit;
 /**
  * Tests for {@link PageLoadMetrics}
  */
+@RunWith(ChromeJUnit4ClassRunner.class)
 @RetryOnFailure
-public class PageLoadMetricsTest extends ChromeActivityTestCaseBase<ChromeActivity> {
-    public PageLoadMetricsTest() {
-        super(ChromeActivity.class);
-    }
+@CommandLineFlags.Add({ChromeSwitches.DISABLE_FIRST_RUN_EXPERIENCE,
+        ChromeActivityTestRule.DISABLE_NETWORK_PREDICTION_FLAG})
+public class PageLoadMetricsTest {
+    @Rule
+    public ChromeActivityTestRule<ChromeActivity> mActivityTestRule =
+            new ChromeActivityTestRule<>(ChromeActivity.class);
 
     private static final int PAGE_LOAD_METRICS_TIMEOUT_MS = 3000;
     private static final String TEST_PAGE = "/chrome/test/data/android/google.html";
@@ -34,17 +48,19 @@ public class PageLoadMetricsTest extends ChromeActivityTestCaseBase<ChromeActivi
     private EmbeddedTestServer mTestServer;
     private PageLoadMetricsObserver mMetricsObserver;
 
-    @Override
-    protected void setUp() throws Exception {
-        super.setUp();
-        mTestServer = EmbeddedTestServer.createAndStartServer(getInstrumentation().getContext());
+    @Before
+    public void setUp() throws Exception {
+        mActivityTestRule.startMainActivityOnBlankPage();
+        mTestServer = EmbeddedTestServer.createAndStartServer(
+                InstrumentationRegistry.getInstrumentation().getContext());
         mTestPage = mTestServer.getURL(TEST_PAGE);
 
-        mMetricsObserver = new PageLoadMetricsObserver(getActivity().getActivityTab());
+        mMetricsObserver =
+                new PageLoadMetricsObserver(mActivityTestRule.getActivity().getActivityTab());
     }
 
-    @Override
-    protected void tearDown() throws Exception {
+    @After
+    public void tearDown() throws Exception {
         ThreadUtils.runOnUiThreadBlocking(new Runnable() {
             @Override
             public void run() {
@@ -53,12 +69,6 @@ public class PageLoadMetricsTest extends ChromeActivityTestCaseBase<ChromeActivi
         });
 
         mTestServer.stopAndDestroyServer();
-        super.tearDown();
-    }
-
-    @Override
-    public void startMainActivity() throws InterruptedException {
-        startMainActivityOnBlankPage();
     }
 
     private static class PageLoadMetricsObserver implements PageLoadMetrics.Observer {
@@ -96,10 +106,11 @@ public class PageLoadMetricsTest extends ChromeActivityTestCaseBase<ChromeActivi
         }
     }
 
+    @Test
     @SmallTest
     public void testPageLoadMetricEmitted() throws InterruptedException {
-        assertFalse("Tab shouldn't be loading anything before we add observer",
-                getActivity().getActivityTab().isLoading());
+        Assert.assertFalse("Tab shouldn't be loading anything before we add observer",
+                mActivityTestRule.getActivity().getActivityTab().isLoading());
         ThreadUtils.runOnUiThreadBlocking(new Runnable() {
             @Override
             public void run() {
@@ -107,11 +118,11 @@ public class PageLoadMetricsTest extends ChromeActivityTestCaseBase<ChromeActivi
             }
         });
 
-        loadUrl(mTestPage);
+        mActivityTestRule.loadUrl(mTestPage);
 
-        assertTrue("First Contentful Paint should be reported",
+        Assert.assertTrue("First Contentful Paint should be reported",
                 mMetricsObserver.waitForFirstContentfulPaintEvent());
-        assertTrue("Load event start event should be reported",
+        Assert.assertTrue("Load event start event should be reported",
                 mMetricsObserver.waitForLoadEventStartEvent());
     }
 }