Turn off OpenLocalMediaFileFullscreen test because it's flaky.

Bug: 903016
Change-Id: I9800b5fb42cf76982c28be85b557b66167bd3d1d
Reviewed-on: https://chromium-review.googlesource.com/c/1325201
Commit-Queue: mark a. foltz <mfoltz@chromium.org>
Reviewed-by: mark a. foltz <mfoltz@chromium.org>
Cr-Commit-Position: refs/heads/master@{#606340}

chrome/test/media_router/media_router_e2e_ui_browsertest.cc

@@ -14,8 +14,9 @@
 
 namespace media_router {
 
+// TODO(crbug.com/903016) Disabled due to flakiness.
 IN_PROC_BROWSER_TEST_F(MediaRouterE2EBrowserTest,
-                       MANUAL_OpenLocalMediaFileFullscreen) {
+                       DISABLED_OpenLocalMediaFileFullscreen) {
   GURL file_url = ui_test_utils::GetTestUrl(
       base::FilePath(base::FilePath::kCurrentDirectory),
       base::FilePath(FILE_PATH_LITERAL("media/bigbuck.webm")));