aw: remove @RetryOnFailure for AwSettingsTest#testDatabaseEnabled

Flakiness dashboard looks green, so remove @RetryOnFailure.

Bug: 767180
Change-Id: I62d513b6c89836af85bf6933bdef18f6e9df468c
Reviewed-on: https://chromium-review.googlesource.com/806318Reviewed-by: Bo <boliu@chromium.org>
Commit-Queue: Shimi Zhang <ctzsm@chromium.org>
Cr-Commit-Position: refs/heads/master@{#521722}

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

@@ -1829,7 +1829,6 @@ public class AwSettingsTest {
     @Test
     @SmallTest
     @Feature({"AndroidWebView", "Preferences"})
-    @RetryOnFailure
     public void testDatabaseEnabled() throws Throwable {
         TestAwContentsClient client = new TestAwContentsClient();
         final AwTestContainerView testContainerView =