Disable PermissionRequestManagerBrowserTest.BackgroundTabNavigation on all platforms.

The test is flaky on all platforms, not just Linux and Mac.

TBR=fdegans@chromium.org

Bug: 931657
Change-Id: Iffe8b086401cedbae7b39c8eb089c93a1e5a1da6
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1980807Reviewed-by: Fabrice de Gans-Riberi <fdegans@chromium.org>
Commit-Queue: Fabrice de Gans-Riberi <fdegans@chromium.org>
Cr-Commit-Position: refs/heads/master@{#727191}

chrome/browser/permissions/permission_request_manager_browsertest.cc

@@ -464,15 +464,10 @@ IN_PROC_BROWSER_TEST_F(PermissionRequestManagerBrowserTest,
   EXPECT_EQ(2, bubble_factory_1->show_count());
 }
 
-// Regularly timing out in Linux and macOS Debug Builds.
+// Regularly timing out in Windows, Linux and macOS Debug Builds.
 // https://crbug.com/931657
-#if defined(OS_LINUX) || defined(OS_MACOSX)
-#define MAYBE_BackgroundTabNavigation DISABLED_BackgroundTabNavigation
-#else
-#define MAYBE_BackgroundTabNavigation BackgroundTabNavigation
-#endif
 IN_PROC_BROWSER_TEST_F(PermissionRequestManagerBrowserTest,
-                       MAYBE_BackgroundTabNavigation) {
+                       DISABLED_BackgroundTabNavigation) {
   ASSERT_TRUE(embedded_test_server()->Start());
 
   ui_test_utils::NavigateToURLBlockUntilNavigationsComplete(