Disable BackgroundFetchBrowserTest.AbortFromUI due to flakiness

Bug: 1056096
Change-Id: Ie4057f5584cf017cc4a6f2933cc289160530b1f4
Tbr: peter@chromium.org
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2072485Reviewed-by: Yutaka Hirano <yhirano@chromium.org>
Commit-Queue: Yutaka Hirano <yhirano@chromium.org>
Cr-Commit-Position: refs/heads/master@{#744582}

chrome/browser/background_fetch/background_fetch_browsertest.cc

@@ -776,7 +776,8 @@ IN_PROC_BROWSER_TEST_F(BackgroundFetchBrowserTest, ClickEventIsDispatched) {
   }
 }
 
-IN_PROC_BROWSER_TEST_F(BackgroundFetchBrowserTest, AbortFromUI) {
+// TODO(crbug.com/1056096): Re-enable this test.
+IN_PROC_BROWSER_TEST_F(BackgroundFetchBrowserTest, DISABLED_AbortFromUI) {
   std::vector<OfflineItem> items;
   // Creates a registration with more than one request.
   ASSERT_NO_FATAL_FAILURE(