Converts WebApkIntegrationTest to JUnit4.

This will allow me to increase code reuse with a nice custom @Rule.

BUG=640116

Review-Url: https://codereview.chromium.org/2854943005
Cr-Commit-Position: refs/heads/master@{#469559}

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

@@ -5,13 +5,23 @@
 package org.chromium.chrome.browser.webapps;
 
 import android.content.Intent;
+import android.support.test.InstrumentationRegistry;
 import android.support.test.filters.LargeTest;
 
+import org.junit.After;
+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.base.test.util.Feature;
 import org.chromium.base.test.util.RetryOnFailure;
 import org.chromium.base.test.util.ScalableTimeout;
+import org.chromium.chrome.browser.ChromeSwitches;
 import org.chromium.chrome.browser.ShortcutHelper;
-import org.chromium.chrome.test.ChromeActivityTestCaseBase;
+import org.chromium.chrome.test.ChromeActivityTestRule;
+import org.chromium.chrome.test.ChromeJUnit4ClassRunner;
 import org.chromium.chrome.test.util.ChromeTabUtils;
 import org.chromium.content.browser.test.util.Criteria;
 import org.chromium.content.browser.test.util.CriteriaHelper;
@@ -19,32 +29,39 @@ import org.chromium.net.test.EmbeddedTestServer;
 import org.chromium.webapk.lib.common.WebApkConstants;
 
 /** Integration tests for WebAPK feature. */
-public class WebApkIntegrationTest extends ChromeActivityTestCaseBase<WebApkActivity> {
+@RunWith(ChromeJUnit4ClassRunner.class)
+@CommandLineFlags.Add({ChromeSwitches.DISABLE_FIRST_RUN_EXPERIENCE,
+        ChromeActivityTestRule.DISABLE_NETWORK_PREDICTION_FLAG})
+public class WebApkIntegrationTest {
+    @Rule
+    public final ChromeActivityTestRule<WebApkActivity> mActivityTestRule =
+            new ChromeActivityTestRule<>(WebApkActivity.class);
+
     private static final long STARTUP_TIMEOUT = ScalableTimeout.scaleTimeout(10000);
 
     private EmbeddedTestServer mTestServer;
 
-    public WebApkIntegrationTest() {
-        super(WebApkActivity.class);
-    }
-
     public void startWebApkActivity(String webApkPackageName, final String startUrl)
             throws InterruptedException {
-        Intent intent = new Intent(getInstrumentation().getTargetContext(), WebApkActivity.class);
+        Intent intent =
+                new Intent(InstrumentationRegistry.getTargetContext(), WebApkActivity.class);
         intent.putExtra(WebApkConstants.EXTRA_WEBAPK_PACKAGE_NAME, webApkPackageName);
         intent.putExtra(ShortcutHelper.EXTRA_URL, startUrl);
         intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
-        setActivity(getInstrumentation().startActivitySync(intent));
-        getInstrumentation().waitForIdleSync();
+        mActivityTestRule.setActivity(
+                (WebApkActivity) InstrumentationRegistry.getInstrumentation().startActivitySync(
+                        intent));
+        InstrumentationRegistry.getInstrumentation().waitForIdleSync();
 
         CriteriaHelper.pollInstrumentationThread(new Criteria() {
             @Override
             public boolean isSatisfied() {
-                return getActivity().getActivityTab() != null;
+                return mActivityTestRule.getActivity().getActivityTab() != null;
             }
         }, STARTUP_TIMEOUT, CriteriaHelper.DEFAULT_POLLING_INTERVAL);
 
-        ChromeTabUtils.waitForTabPageLoaded(getActivity().getActivityTab(), startUrl);
+        ChromeTabUtils.waitForTabPageLoaded(
+                mActivityTestRule.getActivity().getActivityTab(), startUrl);
     }
 
     /** Waits for the splash screen to be hidden. */
@@ -52,33 +69,28 @@ public class WebApkIntegrationTest extends ChromeActivityTestCaseBase<WebApkActi
         CriteriaHelper.pollInstrumentationThread(new Criteria() {
             @Override
             public boolean isSatisfied() {
-                return !getActivity().isSplashScreenVisibleForTests();
+                return !mActivityTestRule.getActivity().isSplashScreenVisibleForTests();
             }
         });
     }
 
-    @Override
-    public final void startMainActivity() throws InterruptedException {
-        // Do nothing
-    }
-
-    @Override
-    protected void setUp() throws Exception {
-        super.setUp();
-        mTestServer = EmbeddedTestServer.createAndStartServer(getInstrumentation().getContext());
+    @Before
+    public void setUp() throws Exception {
+        mTestServer = EmbeddedTestServer.createAndStartServer(
+                InstrumentationRegistry.getInstrumentation().getContext());
         WebApkUpdateManager.setUpdatesEnabledForTesting(false);
     }
 
-    @Override
-    protected void tearDown() throws Exception {
+    @After
+    public void tearDown() throws Exception {
         mTestServer.stopAndDestroyServer();
-        super.tearDown();
     }
 
     /**
      * Test launching a WebAPK. Test that loading the start page works and that the splashscreen
      * eventually hides.
      */
+    @Test
     @LargeTest
     @Feature({"WebApk"})
     @RetryOnFailure