Disable flaky testControlsVisibleAfterExitingVr_WebXr.

Disable org.chromium.chrome.browser.vr_shell.WebVrTransitionTest
testControlsVisibleAfterExitingVr_WebXr, because it is flaky.

TBR=bsheedy@chromium.org

Bug: 841103
Change-Id: I55651a634cfd81b43fd3668660cc3d59eda008a1
Reviewed-on: https://chromium-review.googlesource.com/1052012Reviewed-by: vitaliii <vitaliii@chromium.org>
Commit-Queue: vitaliii <vitaliii@chromium.org>
Cr-Commit-Position: refs/heads/master@{#557181}

chrome/android/javatests/src/org/chromium/chrome/browser/vr_shell/WebVrTransitionTest.java

@@ -375,8 +375,9 @@ public class WebVrTransitionTest {
      */
     @Test
     @MediumTest
-    @CommandLineFlags.Remove({"enable-webvr"})
-    @CommandLineFlags.Add({"enable-features=WebXR"})
+    @DisabledTest(message = "crbug.com/841103")
+    //@CommandLineFlags.Remove({"enable-webvr"})
+    //@CommandLineFlags.Add({"enable-features=WebXR"})
     public void testControlsVisibleAfterExitingVr_WebXr() throws InterruptedException {
         controlsVisibleAfterExitingVrImpl(
                 XrTestFramework.getFileUrlForHtmlTestFile("generic_webxr_page"), mXrTestFramework);