Revert "Disable AwSettingsTest."

This reverts commit b1f4b048.

Reason for revert:
Loses test coverage on hundreds of tests from only a single
DCHECK failure. This did not appear to affect cq so should
not affect developer productivity. Re-enabling and going to
resolve the DCHECK failure instead

Original change's description:
> Disable AwSettingsTest.
> 
> Bug: 1126917
> TBR: boliu@chromium.org
> Change-Id: I77d7c6e12f975cb2cb17f5a9ee015d714f3a559b
> Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2405702
> Commit-Queue: Xi Han <hanxi@chromium.org>
> Reviewed-by: Xi Han <hanxi@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#806206}

TBR=hanxi@chromium.org

# Not skipping CQ checks because original CL landed > 1 day ago.

Bug: 1126917
Change-Id: Idf6793a92576518c0898e736d64912925c6a3196
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2410340Reviewed-by: Bo <boliu@chromium.org>
Commit-Queue: Bo <boliu@chromium.org>
Cr-Commit-Position: refs/heads/master@{#806668}

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

@@ -74,7 +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)
-@DisabledTest(message = "http://crbug.com/1126917")
 public class AwSettingsTest {
     @Rule
     public AwActivityTestRule mActivityTestRule =