Remove ash_unittests/mash_unittests from Windows build targets

mash/example/BUILD.gn

Index: mash/example/BUILD.gn
diff --git a/mash/example/BUILD.gn b/mash/example/BUILD.gn
index e46baab38ddab1daf5bc8d47fd0f4e99b3ba432a..26c0873e35c022f52590bc2135961ba7a0b66490 100644
--- a/mash/example/BUILD.gn
+++ b/mash/example/BUILD.gn
@@ -8,9 +8,13 @@ group("example") {
   testonly = true
 
   deps = [
-    "//ash/mus",
     "//mash/example/views_examples",
     "//mash/example/window_type_launcher",
+    "//mash/simple_wm",
     "//services/service_manager/standalone",
   ]
+
+  if (is_chromeos) {
+    deps += [ "//ash/mus" ]
+  }
 }