Disable TrayAccessibilityTest.ShowMenu on Linux.

Fails on linux-chromeos-dbg.

TBR=yoshiki@chromium.org

BUG: 1027919
Change-Id: I9006192cdc5a8c850f61d9d127b68092bbbf9dca
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1936214Reviewed-by: Tim Schumann <tschumann@chromium.org>
Commit-Queue: Tim Schumann <tschumann@chromium.org>
Cr-Commit-Position: refs/heads/master@{#719088}

chrome/browser/chromeos/system/tray_accessibility_browsertest.cc

@@ -191,7 +191,14 @@ class TrayAccessibilityTest
   std::unique_ptr<ash::SystemTrayTestApi> tray_test_api_;
 };
 
-IN_PROC_BROWSER_TEST_P(TrayAccessibilityTest, ShowMenu) {
+  
+// Fails on linux-chromeos-dbg see crbug/1027919.
+#if defined(OS_LINUX)
+#define MAYBE_ShowMenu DISABLED_ShowMenu
+#else
+#define MAYBE_ShowMenu ShowMenu
+#endif
+IN_PROC_BROWSER_TEST_P(TrayAccessibilityTest, MAYBE_ShowMenu) {
   SetShowAccessibilityOptionsInSystemTrayMenu(false);
 
   // Confirms that the menu is hidden.