Disable flaky test PortalBrowserTest#GestureCleanedUpBeforeActivation on Android

Flaky on recent runs of android waterfall bots.

BUG=990555

TBR=hartmanng@chromium.org,adithyas@chromium.org
NOTRY=true

Change-Id: I2a605b491db96b494f94a20c3451207dc3bd64e1
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1738592Reviewed-by: Tim Volodine <timvolodine@chromium.org>
Commit-Queue: Tim Volodine <timvolodine@chromium.org>
Cr-Commit-Position: refs/heads/master@{#684332}

content/browser/portal/portal_browsertest.cc

@@ -974,7 +974,8 @@ IN_PROC_BROWSER_TEST_F(PortalBrowserTest, TouchStateClearedBeforeActivation) {
 #endif
 
 // TODO(crbug.com/985078): Fix on Mac.
-#if !defined(OS_MACOSX)
+// TODO(crbug.com/991192): Flaky on Android
+#if !defined(OS_MACOSX) && !defined(OS_ANDROID)
 IN_PROC_BROWSER_TEST_F(PortalBrowserTest, GestureCleanedUpBeforeActivation) {
   EXPECT_TRUE(NavigateToURL(
       shell(), embedded_test_server()->GetURL("portal.test", "/title1.html")));