Disable PaymentRequestMetricsTest.testAbortMetrics_OtherAborted_TabClosed

Test is flaky.

TBR: gogerald@chromium.org, rouslan@chromium.org
Bug: 968797
Change-Id: Ifda5c81c08142428ef25cd7093ea823eb68bc639
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1637862Reviewed-by: Shimi Zhang <ctzsm@chromium.org>
Commit-Queue: Shimi Zhang <ctzsm@chromium.org>
Cr-Commit-Position: refs/heads/master@{#664942}

chrome/android/javatests/src/org/chromium/chrome/browser/payments/PaymentRequestMetricsTest.java

@@ -203,6 +203,7 @@ public class PaymentRequestMetricsTest implements MainActivityStartCallback {
     @MediumTest
     @Feature({"Payments"})
     @RetryOnFailure
+    @DisabledTest(message = "Test is flaky, see crbug.com/968797")
     public void testAbortMetrics_OtherAborted_TabClosed()
             throws InterruptedException, TimeoutException {
         mPaymentRequestTestRule.triggerUIAndWait("ccBuy", mPaymentRequestTestRule.getReadyToPay());