Portals: Re-enable PortalsTest.testTouchTransferAfterTouchStartActivate

No changes in test logic.

Bug: 1024850
Change-Id: I9f97de7f1d0a31f7184f0856f025aec219fe79a9
Tbr: dtrainor@chromium.org
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2261159Reviewed-by: Adithya Srinivasan <adithyas@chromium.org>
Commit-Queue: Adithya Srinivasan <adithyas@chromium.org>
Cr-Commit-Position: refs/heads/master@{#781463}

chrome/android/javatests/src/org/chromium/chrome/browser/portals/PortalsTest.java

@@ -319,7 +319,6 @@ public class PortalsTest {
     @Test
     @MediumTest
     @Feature({"Portals"})
-    @DisabledTest // Disabled due to flakiness. See https://crbug.com/1024850
     public void testTouchTransferAfterTouchStartActivate() throws Exception {
         mActivityTestRule.startMainActivityWithURL(mTestServer.getURL(
                 "/chrome/test/data/android/portals/touch-transfer.html?event=touchstart"));