Disable NativeMessagingLaunchBackgroundModeApiTest.Success on Windows

Disabling because of flakiness.

TBR=sergeyu,sammc

Bug: 1030332
Change-Id: Id29f3e5d27d92bb87a003e3afac49d51ad3f3fbf
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1948672Reviewed-by: Takumi Fujimoto <takumif@chromium.org>
Commit-Queue: Takumi Fujimoto <takumif@chromium.org>
Cr-Commit-Position: refs/heads/master@{#721095}

chrome/browser/extensions/api/messaging/native_messaging_apitest.cc

@@ -373,7 +373,14 @@ IN_PROC_BROWSER_TEST_F(NativeMessagingLaunchBackgroundModeApiTest,
   EXPECT_EQ(kExtensionId, extension->id());
 }
 
-IN_PROC_BROWSER_TEST_F(NativeMessagingLaunchBackgroundModeApiTest, Success) {
+// Flaky on a Windows bot. See crbug.com/1030332.
+#if defined(OS_WIN)
+#define MAYBE_Success DISABLED_Success
+#else
+#define MAYBE_Success Success
+#endif
+IN_PROC_BROWSER_TEST_F(NativeMessagingLaunchBackgroundModeApiTest,
+                       MAYBE_Success) {
   EXPECT_TRUE(
       g_browser_process->background_mode_manager()->IsBackgroundModeActive());