Allow building mojo_shell and non-graphical apps/services on a Mac

examples/BUILD.gn

Index: examples/BUILD.gn
diff --git a/examples/BUILD.gn b/examples/BUILD.gn
index c066d8755d54c64c4d04bfc4b278adff5bbe5ff9..62f7b6a39b02ae38c2c009a1683c38229ac4d336 100644
--- a/examples/BUILD.gn
+++ b/examples/BUILD.gn
@@ -27,12 +27,9 @@ group("examples") {
     "//examples/png_viewer",
     "//examples/recursive_content_handler",
     "//examples/spinning_cube",
-    "//examples/surfaces_app",
     "//examples/tiny",
     "//examples/trace_me",
     "//examples/wget",
-    "//examples/window_manager",
-    "//examples/wm_flow",
   ]
 
   if (!is_android) {
@@ -47,6 +44,14 @@ group("examples") {
     ]
   }
 
+  if (is_linux || is_android) {
+    deps += [
+      "//examples/surfaces_app",
+      "//examples/window_manager",
+      "//examples/wm_flow",
+    ]
+  }
+
   if (defined(go_build_tool) && go_build_tool != "") {
     deps += [ "//examples/go" ]
     if (is_android) {