TabindexSaveFileDialog_FileManagerBrowserTest.Test_0/1/2 are failing on cros trunk

Disabled for the official build of cros trunk for now.

BUG=482121
TBR=yoshiki@chromium.org

Review URL: https://codereview.chromium.org/1110883004

Cr-Commit-Position: refs/heads/master@{#327400}

chrome/browser/chromeos/file_manager/file_manager_browsertest.cc

@@ -1169,8 +1169,14 @@ INSTANTIATE_TEST_CASE_P(
         TestParameter(NOT_IN_GUEST_MODE, "tabindexOpenDialogDownloads"),
         TestParameter(IN_GUEST_MODE, "tabindexOpenDialogDownloads")));
 
+// Fails on official build. http://crbug.com/482121.
+#if defined(OFFICIAL_BUILD)
+#define MAYBE_TabindexSaveFileDialog DISABLED_TabindexSaveFileDialog
+#else
+#define MAYBE_TabindexSaveFileDialog TabindexSaveFileDialog
+#endif
 INSTANTIATE_TEST_CASE_P(
-    TabindexSaveFileDialog,
+    MAYBE_TabindexSaveFileDialog,
     FileManagerBrowserTest,
     ::testing::Values(
         TestParameter(NOT_IN_GUEST_MODE, "tabindexSaveFileDialogDrive"),