Disable failing navigation callbacks test

ios/web/web_state/navigation_callbacks_inttest.mm

Index: ios/web/web_state/navigation_callbacks_inttest.mm
diff --git a/ios/web/web_state/navigation_callbacks_inttest.mm b/ios/web/web_state/navigation_callbacks_inttest.mm
index 4b8ea7f8d7999799f8dd59448a25343a40981a22..76e3b92fcd13bf3fa8ceddd66663539b1c5f5034 100644
--- a/ios/web/web_state/navigation_callbacks_inttest.mm
+++ b/ios/web/web_state/navigation_callbacks_inttest.mm
@@ -486,7 +486,13 @@ TEST_F(NavigationCallbacksTest, NativeContentReload) {
 }
 
 // Tests successful navigation to a new page with post HTTP method.
-TEST_F(NavigationCallbacksTest, UserInitiatedPostNavigation) {
+// TODO (crbug/729602): This test is disabled due to failing on iOS 9.3 devices.
+#if TARGET_IPHONE_SIMULATOR
+#define MAYBE_UserInitiatedPostNavigation UserInitiatedPostNavigation
+#else
+#define MAYBE_UserInitiatedPostNavigation DISABLED_UserInitiatedPostNavigation
+#endif
+TEST_F(NavigationCallbacksTest, MAYBE_UserInitiatedPostNavigation) {
   const GURL url = HttpServer::MakeUrl("http://chromium.test");
   std::map<GURL, std::string> responses;
   responses[url] = "Chromium Test";
@@ -535,7 +541,13 @@ TEST_F(NavigationCallbacksTest, RendererInitiatedPostNavigation) {
 }
 
 // Tests successful reload of a page returned for post request.
-TEST_F(NavigationCallbacksTest, ReloadPostNavigation) {
+// TODO (crbug/729602): This test is disabled due to failing on iOS 9.3 devices.
+#if TARGET_IPHONE_SIMULATOR
+#define MAYBE_ReloadPostNavigation ReloadPostNavigation
+#else
+#define MAYBE_ReloadPostNavigation DISABLED_ReloadPostNavigation
+#endif
+TEST_F(NavigationCallbacksTest, MAYBE_ReloadPostNavigation) {
   const GURL url = HttpServer::MakeUrl("http://chromium.test");
   std::map<GURL, std::string> responses;
   const GURL action = HttpServer::MakeUrl("http://action.test");
@@ -580,7 +592,13 @@ TEST_F(NavigationCallbacksTest, ReloadPostNavigation) {
 }
 
 // Tests going forward to a page rendered from post response.
-TEST_F(NavigationCallbacksTest, ForwardPostNavigation) {
+// TODO (crbug/729602): This test is disabled due to failing on iOS 9.3 devices.
+#if TARGET_IPHONE_SIMULATOR
+#define MAYBE_ForwardPostNavigation ForwardPostNavigation
+#else
+#define MAYBE_ForwardPostNavigation DISABLED_ForwardPostNavigation
+#endif
+TEST_F(NavigationCallbacksTest, MAYBE_ForwardPostNavigation) {
   const GURL url = HttpServer::MakeUrl("http://chromium.test");
   std::map<GURL, std::string> responses;
   const GURL action = HttpServer::MakeUrl("http://action.test");