Create ContentShellActivityTestRule and BaseJUnitRunner

content/shell/android/javatests/src/org/chromium/content_shell_apk/ContentShellPreconditionsTest.java

-// Copyright 2012 The Chromium Authors. All rights reserved.
+// Copyright 2017 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.content_shell_apk;
 
 import android.annotation.TargetApi;
 import android.content.Context;
 import android.os.Build;
 import android.os.PowerManager;
+import android.support.test.InstrumentationRegistry;
 import android.support.test.filters.MediumTest;
 
+import org.junit.Assert;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+
+import org.chromium.base.test.BaseJUnit4ClassRunner;
 import org.chromium.base.test.util.Feature;
 
 /**
  * Test that verifies preconditions for tests to run.
  */
-public class ContentShellPreconditionsTest extends ContentShellTestBase {
+@RunWith(BaseJUnit4ClassRunner.class)
+public class ContentShellPreconditionsTest {
+    @Test
     @TargetApi(Build.VERSION_CODES.KITKAT_WATCH)
     @SuppressWarnings("deprecation")
     @MediumTest
     @Feature({"TestInfrastructure"})
     public void testScreenIsOn() throws Exception {
-        PowerManager pm = (PowerManager) getInstrumentation().getContext().getSystemService(
+        PowerManager pm = (PowerManager) InstrumentationRegistry.getContext().getSystemService(
                 Context.POWER_SERVICE);
 
         if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.KITKAT_WATCH) {
-            assertTrue("Many tests will fail if the screen is not on.", pm.isInteractive());
+            Assert.assertTrue("Many tests will fail if the screen is not on.", pm.isInteractive());
         } else {
-            assertTrue("Many tests will fail if the screen is not on.", pm.isScreenOn());
+            Assert.assertTrue("Many tests will fail if the screen is not on.", pm.isScreenOn());
         }
     }
 }