[Payments] Fix the Payment Request histogram check failure in tests.

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

Index: chrome/android/javatests/src/org/chromium/chrome/browser/payments/PaymentRequestTestBase.java
diff --git a/chrome/android/javatests/src/org/chromium/chrome/browser/payments/PaymentRequestTestBase.java b/chrome/android/javatests/src/org/chromium/chrome/browser/payments/PaymentRequestTestBase.java
index 6670a6749dc8f6f0192b3a2c11830e542f42f41f..1595c93b52b331927b2be4ff43317eb31cb3608f 100644
--- a/chrome/android/javatests/src/org/chromium/chrome/browser/payments/PaymentRequestTestBase.java
+++ b/chrome/android/javatests/src/org/chromium/chrome/browser/payments/PaymentRequestTestBase.java
@@ -148,6 +148,13 @@ abstract class PaymentRequestTestBase extends ChromeActivityTestCaseBase<ChromeT
         clickNodeAndWait(nodeId, helper);
     }
 
+    protected void reTriggerUIAndWait(
+            String nodeId, PaymentsCallbackHelper<PaymentRequestUI> helper)
+            throws InterruptedException, ExecutionException, TimeoutException {
+        clickNodeAndWait(nodeId, helper);
+        mUI = helper.getTarget();
+    }
+
     /** Clicks on an HTML node. */
     protected void clickNodeAndWait(String nodeId, CallbackHelper helper)
             throws InterruptedException, ExecutionException, TimeoutException {