AW: unbatch AwSettingsTest

No change to production logic. This unbatches AwSettingsTest. This is to
work around a bug with the @Batch annotation: if a test fails or
crashes, then all subsequent tests have status "unknown" and appear as
failures. We've received several "flaky test" bugs for tests which are
themselves perfectly fine but are failing due to a previous test's
failure.

It seems more effective to unbatch this test suite until
https://crbug.com/1127935 is resolved.

Bug: 1144352
Test: run_webview_instrumentation_test_apk -f AwSettingsTest.*
Change-Id: I8d42330909782d071ee2ffcec028a0171a4ad788
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2515785
Auto-Submit: Nate Fischer <ntfschr@chromium.org>
Commit-Queue: Bo <boliu@chromium.org>
Reviewed-by: Bo <boliu@chromium.org>
Cr-Commit-Position: refs/heads/master@{#823512}

android_webview/javatests/src/org/chromium/android_webview/test/AwSettingsTest.java

@@ -40,7 +40,6 @@ import org.chromium.android_webview.test.util.VideoTestUtil;
 import org.chromium.android_webview.test.util.VideoTestWebServer;
 import org.chromium.base.Callback;
 import org.chromium.base.FileUtils;
-import org.chromium.base.test.util.Batch;
 import org.chromium.base.test.util.CallbackHelper;
 import org.chromium.base.test.util.CommandLineFlags;
 import org.chromium.base.test.util.DisabledTest;
@@ -75,7 +74,6 @@ import java.util.regex.Pattern;
  */
 @RunWith(AwJUnit4ClassRunner.class)
 @CommandLineFlags.Add({ContentSwitches.HOST_RESOLVER_RULES + "=MAP * 127.0.0.1"})
-@Batch(Batch.PER_CLASS)
 public class AwSettingsTest {
     @Rule
     public AwActivityTestRule mActivityTestRule =