Re-enable flaky AppShimInteractiveTest tests

Recent MojoChannel changes may have fixed the flakiness.

Bug: 980072, 913181
Change-Id: Icd92cf9094d5ffe7a6f1f2e5debf19ca0332a8d8
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1690053
Commit-Queue: Raymes Khoury <raymes@chromium.org>
Reviewed-by: Giovanni Ortuño Urquidi <ortuno@chromium.org>
Reviewed-by: Dominick Ng <dominickn@chromium.org>
Cr-Commit-Position: refs/heads/master@{#675864}

chrome/browser/apps/app_shim/app_shim_interactive_uitest_mac.mm

@@ -310,9 +310,9 @@ namespace apps {
 #define MAYBE_ShowWindow DISABLED_ShowWindow
 #define MAYBE_RebuildShim DISABLED_RebuildShim
 #else
-#define MAYBE_Launch DISABLED_Launch  // http://crbug.com/913490
+#define MAYBE_Launch Launch
 #define MAYBE_HostedAppLaunch DISABLED_HostedAppLaunch
-#define MAYBE_ShowWindow DISABLED_ShowWindow  // https://crbug.com/980072
+#define MAYBE_ShowWindow ShowWindow
 // http://crbug.com/517744 HostedAppLaunch fails with open as tab for apps
 // http://crbug.com/509774 this test is flaky so is disabled even in the
 // static build.